Abstract: A novel electro-optically Q-switched laser with short cavity was demonstrated. Its optimal structure parameters were determined via the analysis of factors related to output pulse width. Quasi-continuous end-pumped Nd:YVO4 crystal with concentration of 1.0 % was cut along Brewster angle in a-axis, in order to ensure polarized oscillation. Thus, the cavity length was shortened efficiently due to the omission of quarter wave plate in voltage-decreased Q-switching structure. In condition of 20 mm physical cavity length, the narrowest output pulse width of 1.049 ns, pulse energy of 0.32 mJ and beam quality factor of 1.9 were achieved.