在激光二极管端面抽运的三腔复合镜Nd:YVO4双波长激光器中，通过合理配置两个支腔腔长和输出镜透射率，采用石墨烯分散液作为可饱和吸收体，实现1064 nm和1342 nm双波长激光被动调Q。当1064 nm支腔透射率为20%时，获得脉宽为10.8 ns的1064 nm脉冲和脉宽为12.5 ns的1342 nm脉冲，1064 nm脉冲在前，两脉冲峰值的时间间隔为16 ns；当1064 nm支腔透射率为25%时，获得脉宽为11.3 ns的1064 nm脉冲和脉宽为14.2 ns的1342 nm脉冲，1342 nm脉冲在前，两脉冲峰值的时间间隔为19 ns。根据双波长谱线竞争理论和石墨烯对1064 nm和1342 nm激光的可饱和吸收特性，对上述实验结果给予了合理的理论解释。

Passively Q-switching of dual-wavelength lasers at 1064 nm and 1342 nm is realized in a laser doide (LD) end-pumped three-mirror compound resonator Nd:YVO4 laser using graphene dispersion as the saturable absorber, by setting the cavity lengths and the output mirror transmissivities of two branch cavity appropriatly. When the transmissivity of 1064 nm branch cavity is 20%, both 1064 nm pulse with 10.8 ns duration and 1342 nm pulse with 12.5 ns duration are achieved, and the 1064 nm pulse is in the front, the time interval between two pulses is 16 ns. Both 1064nm pulse with 11.3 ns duration and 1342 nm pulse with 14.2 ns duration are achieved when the transmissivity of 1064 nm branch cavity is 25%, and 1342 nm pulse is in the front, the time interval between two pulses is 19 ns. A reasonable theoretical explanation is given to the above-mentioned experiment according to dual-wavelength line competition and the saturable absorption of grephene in 1064 nm and 1342 nm lasers.