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The study was conducted to know the best method for estimation of reference crop evapotranspiration (ETr) for Nasik station (Latitude 20 degrees 53’ N, Longitude 75 degrees 16’ E and altitude 565.0 m amsl), Maharashtra, India. Reference crop evapotranspiration is a basic parameter in irrigation system design. Six reference crop evapotranspiration methods were used for their daily performances under semi-arid climatic condition. The Penman-Monteith method standardized by FAO was used to compare with the Modified Penman, Hargreaves-Samani, Pan Evaporation, Blanney-Criddle and Radiation methods. Performances of these methods were made on the basis of the least root mean square error (RMSE) and regression analysis (RA). The value of RMSE ranges from 2.01 to 1.09 with the highest in Pan Evaporation method followed by Blamiey-Criddle, Radiation method, modified Penman and Hargreaves-Samani method. Out of six methods Hargreaves-Samani was found to have least root mean square error (RMSE = 1.09 mm/day) and highest correlation coefficient (r=0.99) under semi-arid climatic conditions of Nasik station of Maharashtra.