The effect of constant temperatures on the development time from first instar to adult emergence was studied in Culex eduardoi Casal & García reared at 7, 10, 15, 20, 25, 30 or 33°C. Data were adjusted to the linear degree-day model and the nonlinear Briére model. According to the linear model, the development time was inversely related to the rearing temperatures between 7°C and 25°C. Maximum mortality (100%) was recorded at temperatures > 30°C. According to the linear model, the development threshold temperature and thermal constant were 5.7°C and 188.8 degree days, respectively. The lower and upper threshold temperatures and the optimum temperature for the nonlinear model were -2.3, 30.0 and 28.1°C, respectively.