In order to study the effects of biofertilizer and phosphate fertilizer on yield and yield components of spring wheat a factorial experiment based on randomized completed blocks design with replications was conducted at the Mohsenabad, Mehran Research station in Ilam, Iran during 2009-2010. Experimental factors consisted of phosphorus chemical fertilizers at four levels(0, 90, 135 and 180 kg ha-1) and bio-fertilizer at four levels (non-inoculation, inoculating with Azotobacter chroococcum, Pseudomonas Putida and Azotobacter plus Pseudomonas). Results of analysis variance showed that using chemical fertilizer significantly effected grain yield, harvest index, biological yield, plant height and protein content. The highest grain and biological yields were produced by applying180 kg ha-1, while its effects on other traits were not significantly different from that of 135 kg ha-1. Biological fertilizers, on the other hand increased grain yield, harvest index, biological yield, plant height and protein content as compared to non inoculation treatment. The highest grain yield, harvest index, biological yield, plant height and protein content obtained from application of Azotobacter plus Pseudomonas. Grain yield, harvest index, biological, plant height were affected by interaction effects of chemical fertilizer and biological fertilizers. The highest and lowest grain yield belonged to the application of 180 kg ha-1 of chemical fertilizer and Azotobacter plus Pseudomonas and non- chemical fertilizer and non-inoculation, respectively, but the difference between 135 and 180 kg.ha-1 was not statistically different. Thus, it is cheaper to recommend use of 135 kg ha-1 of chemical fertilizer and Azotobacter plus Pseudomonas to get acceptable grain and biological yields