The steel body structure of Type 25 bus is a thin-walled cylindrical body structure without center sill, which is welded by underframe, side wall, roof and end wall. Side wall panel, end wall panel, roof panel, corrugated floor and flat floor are welded on the side wall, end wall, roof steel skeleton and underframe steel skeleton respectively to form a closed shell with an arc upper part and a rectangular lower part. The shell is reinforced by longitudinal beams, cross beams and columns, and air conditioners, large windows and new bogies are used.

The car body of series 25 buses is 25.5 meters long, 3. 105 meters wide and 4.433 meters high, and the minimum curve radius is 145 meters ... The structural characteristics of series 25 buses are as follows: the car body is a fully welded structure, consisting of chassis, side walls, end walls and roof.

25 passenger cars of 1993 series were finally determined as the main passenger cars of China Railway. Type 25 buses include 25.5m light high-speed trains, 25.5m Guangzhou-Kowloon air-conditioned trains, 25 trunk air-conditioned buses, 25 Sanmao buses and 25 double-decker air-conditioned buses. Subsequently, a series of products were developed for the Type 25 bus, which were divided into series models such as 25A, 25B, 25D, 25G, 25Z, 25K and 25 T. By 1994, the Type 25 bus series was put into production and began to replace the Type 22 bus. In addition, there is a 25o bus imported from Britain.

In addition to the first trial-produced railway passenger cars, the main models of Type 25 passenger cars are 25A, 25B, 25B, 25T (domestic first-generation 200km/h high-speed passenger cars), 25G, 25Z, 25K and 25T. Type 25 passenger cars include hard seat car (YZ), soft seat car (RZ), hard sleeper car (YW), soft sleeper car (RW), dining car (CA), air conditioning generator car (KD), luggage car (XL) and other types, as well as special test cars and track inspection cars.