The invention discloses a wind generating set rotor barring gear system and a barring gear module thereof. The barring gear module comprises a first barring gear main body, a second barring gear mainbody and a locking part; the second barring gear main body is provided with a pin device used for being in locking cooperation with a rotor, the second barring gear main body is supported on the firstbarring gear main body ,and the second barring gear main body is adjustable relative to the first barring gear main body in a direction that a pin of the pin device is inserted into the rotor. According to the barring gear module, the position of the second barring gear main body is adjustable relative to the first barring gear main body in the pin insertion direction, the assembling position ofthe pin does not need to be considered during first barring gear main body installation, an optimal position of connecting between the rotor and the second barring gear main body can be selected through adjusting the position of the second barring gear main body, the installation efficiency of the barring gear system is facilitated, and the second barring gear main body and the first barring gearmain body are locked to a working position of a barring gear through the locking part, so that the stability and the reliability of the barring gear are further improved.