The Nd∶YVO4 crystal generally applies 808 nm laser as the pumping source, but its strong absorption leads to serious thermal effect, which limits the laser output power and beam quality. In this paper, the 888 nm laser with relatively weak absorption is used as the in-band pumped source, which significantly reduces the thermal effect of Nd∶YVO4 crystal under high pump power. Combined with our self-developed all-fiber picosecond seed laser, the 1 064 nm picosecond laser output with pulse width of 12.1 ps, repetition frequency of 100~500 kHz, max single-pulse energy of 250 μJ is realized. The regenerative amplifier has the advantages of small size, stable pulse, high single-pulse energy, high conversion efficiency and good beam quality. It can be used as the laser source of ultrafast laser processing system or after further amplification.