The laser-diode (LD)-pumped passively Q-switched c-cut Nd:YVO4 self-Raman laser in which Cr4+:YAG crystal is taken as saturable absorber is investigated experimentally. By using Cr4+:YAG crystals with different initial transmissions and output couplers with different reflectivities at Raman laser in the experiment, the influences of the initial transmission and reflectivity on output characteristics of Raman laser are studied. The average output power, pulse repetition frequency and pulse width of Raman laser with respect to the pumped power are measured. The obtained maximum output average power of Raman laser is 370 mW at 4.8 W of pumped power and the corresponding conversion efficiency is 7.7%. The self-Raman laser can produce pulses in the sub nanosecond level, and the maximum single pulse energy and peak power are 54 μJ and 47 kW, respectively.