Salwa Zeidan (née Hussainy) was born in 1956 in the Bekaa Valley, Lebanon, and attended Schmustar Secondary School in Baalbek. A self-taught artist, Zeidan was encouraged to pursue painting by Lebanese artist Pierre Chedid, under whose guidance her informal training began. She honed her skills by practicing classical painting compositions and techniques while immersing herself in the study of diverse artistic styles. Between 1988 and 1989, she audited art and philosophy courses at the Lebanese American University (Byblos Campus), including studio sessions with Paul Guiragossian.

In 1989, Zeidan was invited to organize and participate in the Contemporary Lebanese Artist exhibition at the Meridien Hotel in Abu Dhabi, alongside sixteen other artists, including her mentor Pierre Chedid. That same year, she relocated to Abu Dhabi, where she met Emirati poet Thani Al-Suwaidi, who introduced her to a group of pioneering Emirati artists instrumental in establishing the country's emerging art scene, notable among them contemporary artist Hassan Sharif. Zeidan was quickly embraced by this community of artists and writers, joining their regular gatherings at Sharif's home.

In the years following her arrival in Abu Dhabi, Zeidan continued to create art and curate exhibitions. She held her first solo exhibition in her home and organized multiple shows for both local and international artists in rented hotel ballrooms, funded by proceeds from artwork sales. Zeidan also participated in group exhibitions, including the Abu Dhabi Cultural Foundation's annual Spring Exhibitions between 1992 and 1994, winning second prize in painting in 1992. Recognizing her ability to create and sustain spaces for artists, Hassan Sharif encouraged her to open her own gallery. In 1994, she founded the Bernard Cassia and Salwa Zeidan Art Gallery, the first gallery in the UAE to specialize in abstract art. As curator and director, she inaugurated the gallery with her second solo exhibition, opened by His Highness Sheikh Abdullah Bin Zayed Al Nahyan. Her third solo exhibition, organized in collaboration with the Cultural Foundation in 1995, was held under the patronage of the Lebanese ambassador to the UAE, Sheikh Amine El Khazen. Following the gallery's closure in 1996, Zeidan returned to Lebanon, using the move as an opportunity to focus on her artistic practice.

Upon her return to Lebanon, Zeidan began experimenting with sculpture, first producing mixed-media paintings and later designing stone sculptures inspired by the fluidity of her painted forms. She participated in numerous group exhibitions and held solo shows in Lebanon, Paris, and Switzerland, among others. Zeidan also became an advocate for global peace through art, frequently dedicating proceeds from her exhibitions to humanitarian causes. In 1999, the Royal Academy of Science International Trust invited her to exhibit in London as part of its Culture for Peace program. As a committee member of the Byblos International Contemporary Art and Culture Association, Zeidan helped organize the Byblos Symposium for Sculpture and Painting in 2003. The symposium, held under the theme "History and Life of Byblos," was the first of its kind in the city, hosting thirteen artists over three weeks with the goal of engaging the public with contemporary art and establishing a permanent public art collection in Byblos.

That same year, Zeidan participated in the fourth International Biennale of Contemporary Art in Florence, Italy, where she placed fourth in the drawing and graphic category. In 2006, Zeidan accepted the Worldwide Peace Marker Project (WPMP) Artist Ambassadorship to Lebanon. The WPMP is a work of installation art designed by artist Tiite Baquero, intended as a global collaborative of 199 artists, including 198 global ambassadors. Coordinated by Zeidan and inaugurated by the Minister of Culture and the mayor of Jbeil, the Point of Peace in Lebanon was unveiled in the garden of the International Center for Human Sciences during the Byblos 7000 Years of History celebration.

In 2009, Zeidan returned to Abu Dhabi to reopen her gallery under a new name, the Salwa Zeidan Gallery, inaugurating it with an exhibition of contemporary Emirati art. Building upon her experience at the Byblos Sculpture Symposium, Zeidan served as Symposium Director of the 2010 Abu Dhabi International Sculpture Symposium. Since then, she has continued to curate exhibitions and exhibit her paintings and sculptures internationally.

Salwa Zeidan has exhibited widely throughout her career and curated numerous exhibitions as a gallerist and independent artist. Her works are held in public and private collections internationally, including in Switzerland, Italy, London, France, Turkey, Lebanon, and the UAE.

The Bernard Cassia and Salwa Zeidan Gallery was established in 1994 by Lebanese artist Salwa Zeidan (b. 1956), with the support of Lebanese architect and interior designer Bernard Cassia (1936–2022). The gallery was the first in the United Arab Emirates to specialize in abstract art. Zeidan served as director and curator, while Cassia provided the exhibition space, located on the commercial floor of a residential building on Al Nasser Street in Abu Dhabi. The gallery was inaugurated with Zeidan's second solo exhibition.

Between 1994 and 1997, the Bernard Cassia and Salwa Zeidan Gallery organized several exhibitions featuring artists presented in Abu Dhabi for the first time, including Emirati artist Mohammed Kazem's first solo exhibition in the city. Despite its pioneering role, the gallery was unable to generate sufficient revenue to offset its rental costs and closed in 1996.

In 2005, Christie's opened its first Middle Eastern office, becoming the first international auction house to operate in the UAE. Its inaugural auction in May 2006 confirmed the presence of a robust regional art market, motivating Zeidan to reopen her gallery. She returned to Abu Dhabi in 2008 and, in January 2009, reopened the Salwa Zeidan Gallery in a new location on Al Khaleej Al Arabi Street. The reopening exhibition, Contemporary Emirati Artists, was held under the patronage of His Excellency Sheikh Nahyan Bin Mubarak Al Nahyan and featured nine Emirati artists, including Hassan and Hussain Sharif, Mohamed Kazem, Mohamed Ahmed Ibrahim, and Layla Juma Rashid, showcasing forty works of art.

In 2010, the Salwa Zeidan Gallery collaborated with Zayed University, Abu Dhabi Municipality, and the Armed Forces Officers' Club to present the Abu Dhabi International Sculpture Symposium, under the guidance of His Excellency Sheikh Nahyan bin Mubarak Al Nahyan, then Minister of Higher Education and Scientific Research and President of Zayed University. Under the theme "Bridging Societies through the Language of Art," 17 international artists were selected from among 400 applicants to create large-scale sculptures commissioned by Abu Dhabi at a site custom-built by the Armed Forces Officers' Club. The symposium consisted of six weeks of public programs and lectures held by the visiting artists at Zayed University. The completed sculptures were unveiled at the closing ceremony with the intention of placing them at permanent sites throughout the city.

The Salwa Zeidan Gallery has since held two reopenings: in 2012, when it relocated to a commercial space on Saadiyat Island, and in 2018, when it moved to its current location at the Millennium Al Rawdah Hotel. The gallery represents numerous regional and international artists, including Emirati artist Hussain Sharif, and has collaborated with major institutions such as Sotheby's, Christie's, and the Guggenheim Abu Dhabi. It has participated in every Art Abu Dhabi fair since its reopening in 2009.