The nanosecond-scale laser pulse generation technology with high adjustment precision for laser fusion driver is investigated. By employing a laser diode with central wavelength of 980 nm as reference light and controlling the bias point automatically, an amplitude modulator operating in the pulse mode is implemented. All-fiber laser pulse generation device based on the master oscillator power amplifier structure is established by using high speed electro-optic modulation technology and two-level amplitude modulators simultaneously. The initial precise pulse shaping of input single frequency continuous laser is done by the first amplitude modulator, and the secondary pulse shaping and decreasing noise of temporal shaped pulses are done by the other one. The experimental results show that the device can generate arbitrary shaped pulses with contrast ratio larger than 20001 and pulse duration of 0.1~50.0 ns, which satisfies the requirement of powerful control capability of laser pulse generation device.