The aim of the study was to investigate the chemical fertilizer use levels of grown crops in Isparta province, Turkey and economic loses because of excessive fertilizer used by comparing of fertilizer amount recommended by Agricultural Research Institute and farmer's fertilizer application. In addition, in this study was examined the levels of awareness on the fertilizing of farmers and discussed about negative effects of excessive fertilizer use on environment. Data were obtained by conducting a questionnaire with 100 farms selected by stratified random sampling method. The result indicates that there was no effective and balanced fertilizing in the examined area. Fertilizing without taking into account the results of soil analysis was common in research area. This situation shows that farmers haven't sufficient knowledge on the fertilizing. The level of farmers' environmental awareness was low. It was determined that farmers were used more fertilizer than recommended by Agricultural Research Institute. Economic losses due to excessive fertilizer usage in apple, barley, wheat, cherry, chick pea, sour cherry, peach, apricot, rose, sugar beet, poppy seed, tomato, green lentil were between 1.00-137.24 TL ha(-1). Economic losses due to extra fertilizer use was 57.90 TL ha(-1) and total economic losses were 27 751.17 TL (1 USD=1.34). Economic loss ratios for every crop type were 64.51% for apple, 16.02% for barley, 11.01% for wheat, 4.10% for sugar beet 1.52% for cherry and 2.84% for other crops.