Technical efficiency and low cost production are crucial for competitiveness of tomato growing farms. Therefore, the aim of the present study was to determine production cost and technical efficiency levels of farms that grow tomato in open fields. Experimental data were obtained from 50 randomly selected tomato producers. Results showed that unit production cost of tomato was $0.17 kg(-1) and labor costs had the highest share of total cost. For the estimation of farm level technical efficiency coefficients, Stochastic Frontier Analysis method was used. Technical efficiency coefficients of tomato producing farms varied from 0.35 to 1.00, and the mean was 0.57. Results of Stochastic Frontier Analysis model showed that input use in tomato production could be lowered by 43%. It was found that inefficiencies of farms were mostly due to preventable technical factors rather than due to random causes. Farms could work at full efficiency by lowering their input use as well as by controlling off farm factors. The study suggested that technical training for tomato growing and extension programs would be useful to increase the efficiencies of tomato growing farms.