As a representative of Hong Kong vernacular residential building, Tong lau has played a significant role in Hong Kong's architectural history. Thus, the buildings' preservation is also crucial. However, due to various factors, the preservation work has encountered many obstacles and difficulties. The thesis hopes to explore the influence of local Cantonese film on the preservation of Hong Kong Tong lau from 1950 to the present. As one of Hong Kong's most crucial entertainment industries, native Cantonese films have a profound impact on shaping Hong Kong's identity and creating a collective memory of the local community. Thus, through film study combined with research on Tong lau's preservation history, the thesis intends to explore how local film managed to impact Tong lau's preservation through the continuous enhancement and shaping of collective memories to strengthen identity, and to enrich the narrative of Tong lau's significance and value. Moreover, by studying the association between Tong lau's historical preservation events and local Cantonese film, the thesis aims to provide support for Tong lau's preservation.