Field experiments were conducted to study effect of adding mineral nitrogen as Ammonium nitrate compared with or without two types of organic manuals e.g. Chechen and sheep manuals in presence or absence of inoculums of two strains of Aztobacter vinelandii on the growth and chemical composition of squash plants. Obtained date revealed that all treatment led to significant increase in all growth parameter i.e. plant height, number of level per plant and dry weight.  Chemical analysis also show significant increase in percentage of nitrogen in treated plants compared with control treatment. Also N up take (gm/ plant) was increased in all treatments. Clear variations among different treatments were detected. The highest values in growth permeates or plant chemical composition were obtained when 45 kg of mineral N combined with 7 tons of Chechen manure in presence of Azotobacter isolate T 26. Data also show that Azotobacter isolate T 26 showed more effect on promoting growth compare with isolate T 16. Adding Chechen manure increased all parameters under test compare with sheep manure. Positive correlation between increase mineral nitrogen and growth parameter under test when mineral nitrogen was added alone. On the contrary when mineral nitrogen was compared with any other treatment a clear negative relation between increase the N dose from 45 to 60 and most parameter under test.