The work aims to study the design method of modern trams with the characteristics of Tianfu culture in combination with cultural bionic design. The theoretical basis of modern trams, Tianfu culture and cultural bionics was summarized. Based on cultural bionics, typical cases of modern tram appearance design at home and abroad were analyzed, and the design method and process of modern trams was proposed based on Tianfu culture bionics. The research and analysis of Tianfu culture of the body layer, behavior layer and value layer were carried out, and the typical cultural elements of Tianfu region were summarized. A kind of Tianfu culture elements were selected by fuzzy comprehensive evaluation method, coupled with the representation stage and image stage of cultural bionics, and the result was applied to the appearance design of modern trams. The Sichuan Opera facial mask was taken as a cultural bionic object to simplify its prominent features, and the form and color were integrated into the styling and painting design of 100% low-floor modern trams. Through cultural bionics practice cases, it is shown that cultural bionics can spread the Tianfu culture through the appearance design of urban trams, which provides theoretical reference for the study of the appearance design of modern urban trams.