The Church of Jesus Christ of Latter-day Saints occupied Kom Tong Hall from 1960 to 2004, using it for worship services and as the administrative headquarters for its Asia-area operations. When the Church outgrew the space and moved to a new 14-storey building on Gloucester Road in Wan Chai, it faced a decision: sell the property intact or demolish it for the higher price a vacant lot would fetch. In October 2002, the Church submitted a demolition permit application to the Building Authority. Community concern followed, and after negotiations with the Hong Kong Government, the Church agreed to sell the building intact. In February 2004, the government acquired it for HK$53 million and announced a conversion budget of HK$91.3 million. The restored museum opened on 12 December 2006, marking what would have been Sun Yat-sen's 140th birthday. The Antiquities and Monuments Office declared it a monument on 12 November 2010.

Kom Tong Hall is one of the more extravagant pieces of Edwardian architecture in Hong Kong. Greek-style granite columns frame the facade. Red brick walls rise around windows and doors dressed in granite. Ornate ironwork decorates the balconies. Inside, Baroque and Rococo excess is everywhere: a grand staircase with carved wooden railings and ornamental balustrading climbs from basement to second floor, the ceiling panels of the main rooms are adorned in moulded plaster highlighted with gold leaf, and Art Nouveau stained-glass windows line the main staircase and other prominent positions. Crystal chandeliers, hardwood wainscoting, fireplaces, patterned floor tiles, and wooden louvre windows complete the picture. The Hall occupies roughly 2,560 square metres across four storeys and was among the first buildings in Hong Kong constructed with a steel frame and concealed built-in electrical wiring.

Among the details that make Kom Tong Hall legible as a document of its era is a subtle architectural division: the Hall has two staircases. One at the front was for use by the Ho family; one at the back served the mui tsai — the domestic servants, typically young girls from poor families placed in household service, a practice that persisted in Hong Kong into the mid-twentieth century. The staircases encode a social hierarchy that the museum now asks visitors to reckon with. The Baptist font installed during the decades of Church occupancy was preserved at the government's request as an acknowledgement of that period in the building's history. A plaque on the facade still notes that the Church maintained the Hall well and left behind a cultural legacy.

The museum's exhibitions focus on something the city itself sometimes overlooks: how central Hong Kong was to the revolution that created modern China. Sun came here for secondary school and stayed for his medical education at the College of Medicine for Chinese on Hollywood Road, graduating in 1892. He established the Revive China Society's headquarters in Hong Kong in 1894, using the relative freedom of the British colony to organise what would have been impossible on the Qing mainland. He met comrades at To Tsai Church on Hollywood Road. He used a trading house on Staunton Street as cover. The exhibitions in Kom Tong Hall trace this geography of conspiracy through documents, photographs, and interactive displays. Audio guides are available in Cantonese, Mandarin, and English; the museum is accessible on foot from Sheung Wan MTR station.