The China Railways YJ (Chinese: 跃进; pinyin: Yuè Jìn; lit.

'leap forward') design is based on China Railways PL2 class 2-6-2, itself derived from the JF6 2-8-2, the predecessor of the well known SY class mikado.

According to Chinese sources a total of 202 locos were produced between 1958 and 1961.

[1] At least two YJs are preserved.

YJ 232 is at Baotou Steelworks, YJ 269 is at Diaobingshan, Tiefa, Liaoning.