Abstarct: Foliar nutrition as a supplemental provider of macro and micronutrients, plant hormones, growth stimulants and other useful elements has been used. Effect of foliar fertilization in increasing yield, resistance to diseases and pests, and improve drought tolerance and yield enhancement is observed. Urea foliar application proposed from the early 1950 and has several advantages compared to the use of the earths. In order to study the effect of amount and time of urea foliar applications on quantitative and qualitative characteristics of forage corn and sorghum (single cross 704, speed feed) an experiment was carried out in a farmer corn field in Neyshabour during 2011 crop season. A Split plot factorial arrangement and three replications were used. Treatments were timing of urea application (a week before tasselling, mid anthesis and early milk stage), and urea levels (zero, 5 and 7.5 gl-1) on silage corn and sorghum. According to ANOVA results, the effects of nitrogen level on the forage yield, silage protein was significant. Urea concentrations have significant effect on most of characteristics. Highest forage yield, was achieved at 7.5 gl-1 of urea and highest silage protein was achieved at 5 and 7.5 gl-1 of urea. The results of this study showed that time of urea foliar application have significant effect on leaf area, chlorophyl and leaf protein. The interaction of plant and urea concentrations showed a significant effect on plant height, single wet weight and single dry weight. Also the interaction of plant and time of urea application showed a significant effect on chlorophyl, leaf protein and stem diameter. Intraction of plant, time and concentration of urea had no significant effect on traits. Overall we can say that urea foliar application in appropriate concentration and time can play an impotrtant role in increases the quantitative and qualitative characteristics and above all silage protein that today is one of the biggest concerns of farmers and ranchers. Also reduses the adserve effects of urea fertilizers that threating groundwater and human health.