It was rebuilt from the original Tianjin Metro line, which opened in 1976, but had to close down and undergo renovations in 2001 as part of the system's modernizing project.

After construction resumed, the total length was 7.4 km, with 8 stations, and service on the line began on 28 December 1984.

[citation needed] To cut construction costs, the authority used an abandoned canal bed to build part of the system.

[citation needed] On 28 December 2019, four stations on the eastern extension (Gaozhuangzi, Beiyangcun, Guozhanlu, Donggulu) were opened.

The line passes through six districts, namely Beichen, Hongqiao, Nankai, Heping, Hexi and Jinnan.

All line 1 station concourses are equipped with a customer service center, ticket vending machines, automatic fare gates, and bank ATMs.

TVs are installed that display travel tips, advertising, alerts, and waiting time for the next train.