In this study the amount of energy consumption and its relation with yield in producing two cultivars of plum, Ghatreh Tala and Shablon cultivars, in Tehran province of Iran were studied. For each one of plum cultivars, data were obtained from 100 farmers in the form of personal interview using structured questionnaire method in Tehran province of Iran. Total input energy was found to be 192,652.55 and 168,783.94 MJ ha(-1) for Ghatreh Tala and Shablon cultivars production. In Ghatreh Tala and Shablon cultivars production among input energy sources, electricity energy had the highest share with shares of 79.07% and 80.28% of total input energy respectively. Cobb-Douglass production function was used to determine a relation between input energies and yield in both productions. Results indicated that by using Cobb-Douglass production function to determine mathematical relationship between energy input and yield, human labor energy had the highest impact on yield for both productions. Sensitivity analysis indicated that among the energy inputs human labor energy had the highest MPP value for both plum cultivars productions. The benefit-cost ratios from Ghatreh Tala and Shablon productions were calculated to be 4.18 and 2.46, respectively. (C) 2012 Elsevier Ltd. All rights reserved.