An all-solid-state, high-brightness and sub-nanosecond 1.319 μm continuous active mode-mocked laser was reported. The oscillator was adopted folded thermal stabilized cavity with four mirrors. The gain modules were two NdYAG modules pumped by diodes. The laser was mode-locked by an active amplitude-modulated acousto-optic mode-locker(AOM). An average output power of up to 9.6 W with an excellent stability and beam quality with a M2-value lower than 2 was obtained when the laser was mode-locked. The repetition rate was 100 MHz and the pulse width was about 630 ps.