This investigation was conducted in plastic greenhouses at Sakha Agricultural Research Station to study the effect of different cultivation media, irrigation water sources andorganic manure levels onfresh yieldof cucumber and tomato and NPK contents of leaves and C/N ratio of rice bales .Split-split plot design with four replicates was used. The obtained results could be summarized as follows: 1. Fresh yield of cucumber grown on rice straw bales was increased significantly compared to clay soil, while tomato fresh yield grown on clay soil was higher than that grown on rice straw bales. 2. Fresh yield of either cucumber or tomato was decreased significantly with irrigation by well water or blended fresh with well water compared to fresh water. 3. Addition 20 ton of organic manure /fed. gave the highest fresh yield of cucumber or tomato, while zero level leads to achieve the  lowest yield. 4. N and P contents of cucumber leaves were higher under cultivation on clay soil than rice straw bales, while the K took the opposite trend. Concerning the irrigation water sources, the contents of these elements were higher with fresh water than blended and well water, as well as, addition 20 ton organic manure /fed led to achieve the highest values of NPK content of cucumber and tomato leaves compared to other levels... 5. The C/N ratio of rice straw bales is decreased after cucumber and tomato harvesting comparing to that before the experiment. Using fresh water or blended water gave the lowest value of C/N ratio with cucumber and tomato .The increase of O.M application level up to 20 ton/fed  leads to decrease C/N ratio with both growing crops in both seasons .