This paper investigates effect of gasoline price liberalization on price elasticity of gasoline demand. By using a model where a consumer optimizes her gasoline consumption and number of visits to gas station, we derive price elasticity of gasoline demand and its response to variation of size and frequency in price changes. It shows that price elasticity is decreased with increase in the size and frequency when the price rises. Since price liberalization increases the frequency but reduces the size, the effect of the liberalization on the price elasticity may not be determined. However, price liberalization can make the elasticity higher when the size reduction effect exceeds the frequency increase effect, which the size reduction effect exceed the frequency increase effect, which is consistent with empirical evidence provided by existing studies.