The current injection is a daunting problem in designing and fabricating electrically driven single-cell photonic crystal microcavity laser, and the current path often decreases the quality factor of the microcavity. The electrically driven single-cell photonic crystal microcavity laser is studied with three-dimensional finite-difference time-domain. The eigen mode distribution of the microcavity is given, and accordingly the monopole mode is chosen and investigated.Numerical simulation shows that, under the condition of C6V symmetry, the positions micro-tuning of the six poles nearest the cavity center will result in slow change of the optical field of the monopole mode in the cavity marigin. The quality factor and Purcell factor are raised 7 times, and the laser threshold decreases to one seventh of the original value.