Electrical and optical properties of silicon microscale wire (SiMW) solar cells were investigated. Diverse designs were applied for SiMW geometries as light absorbers. Finite-difference time-domain simulation shows a focused optical field in the wires inducing an optical absorption enhancement in SiMW solar cells. SiMW solar cells provided remarkably higher Voc values (0.597-0.61 V) than that of the planar solar cell (0.587 V). As for the electrical aspects, the position of the space charge region in a SiMW directly affects the carrier collection efficiency according to the SiMW diameter and significantly modulates the photogenerated-currents and voltages in solar cells.