Abstract: Based on reasonable boundary conditions for inflow performance relationships(IPR), a new IPR equatlon for solution gas drive vertical well is presented. It overlaps Vogel’s equation and Fetkovich’s equation, and can be used extensively in solution gas drive reservoirs. Influential factors’ sensitivity analysis of inflow per formance showed that saturated pressure of crude oil was the major factor to affect IPR curvature, meanwhile, a functional relation between equation exponent and saturation pressure was obtained. Through the study of productivity variatlon under dlfferent damage degrees, a calibration equation for inflow performance influenced by damage factors was obtained.