Abstract: Background and Objective: Microelements are essential nutrients for plant growth and development. Chitosan is well-known as an effective Plant Growth Promoter (PGP), which has been widely used in agriculture production. In this study, formulations of microelements and low molecular weight chitosan were prepared to provide micronutrients and PGP agents for tomato through foliar application. Materials and Methods: Four foliar fertilizers were prepared from microelement formulation and low molecular weight chitosan for tomato. The experiments were laid out in split plots with three replications. The yield attributes, yield and quality of tomato fruits were investigated to evaluate the effects of different foliar fertilizers on tomato plants. Results: The study indicated that foliar spraying of microelements and low molecular weight chitosan significantly improved the fruiting and production of tomato. The foliar fertilizer containing high chitosan content and low concentration of microelements (MF-3) produced the highest tomato yield. Total yield and marketable yield of tomato reached 27.25 kg per plot and 55.23 tons per ha, respectively. These values were about 16.8% higher than those of the control. Experimental results also revealed that total vitamin C content in the fruits harvested from the treated plants much higher than that of the control, though their total soluble solid and protein contents were slightly reduced by spraying with foliar fertilizers. Conclusion: Foliar fertilizers composed of microelement and chitosan can be applied to increase the yield and quality of tomato fruits.