Life cycle study of a product is an accepted method for determining the side effects of its production process on environment during its complete life cycle. In this research, the impacts of global warming, acidification, terrestrial eutrophication and fossil resources depletion per unit yield of wheat (ton) on environment were investigated using life cycle assessment method in Marvdasht region of Fars province, and then the contribution of these impacts were determined in the country environmental effects as per capita. Information and dada were obtained through interviews, questionnaires and Agricultural Organization of Marvdasht city, Agriculture and Regional Service Centers. In this research, urea as a nitrogen fertilizer and gas oil were considered as two main inputs of wheat production system which make environmental impact. Gas oil and nitrogen used for unit yield of wheat (ton) in Marvdasht area were calculated as 21 liter and 21.3 kg, respectively. Global warming, acidification, terrestrial eutrophication and fossil resources depletion of one ton wheat production were obtained 262.09 kg co2 eq, 7.35 kg SO2 eq, 19.42 kg NOx eq and 723.04 MJ using life cycle assessment method, respectively. Normalized indicator of global warming, acidification, terrestrial eutrophication and fossil resources depletion of one ton wheat production for Iran condition were obtained 0.032, 0.141, 0.308 and 0.018, respectively. In general, nitrogen component emission due to fertilizer consumption was recognized as the most effective factor on environmental impact of wheat production.