A passively mode-locked Nd∶YVO4 laser operating at 1064 nm is reported with a thermal-stable resonator design.In addition,through the introduction of a Herriott-type multi-pass cavity (MPC),the cavity length is extended to 38.7 m under the invariability of the mode-locking condition.A fiber-coupled 808 nm laser diode is used to end-pump an Nd∶YVO4 crystal with a semiconductor saturable absorber mirror (SESAM) as the passive mode-locking component,and picosecond pulse with a low repetition rate of 3.9 MHz and pulse duration of 60 ps are obtained.When pump power is 10 W,the average output power is 2.6 W,corresponding to a single pulse energy of 0.67 μJ,while the M2 factors in the x and y directions are 1.01 and 1.11,respectively.