The climatic betas play an important role in the detennioation of the yield of any crop, ether directly or indirectly, where they affect wowth, production qualty and quantity. Tina study alms to vet* the most importer/ dirnabc parameters, (temperature) and the economic effects on the yield of tomato, potato and cucumber cops grown to the summer season at various Egyptian climatic tones during the period or (1990-2005). The study restated that In key the effect of the temperature was very oiticat parameter on the tomato *la at the Northern Delta, where they caused a preducbelly decease by 0.67 tonifeddan. On the ether hand, ternperabes that In February and March caused an Increase in tomato yield by 0.33 and 0.36 tonesifeddan respectively, at the southern Delta and Middle Egypt. Moreover, temperature during March at Upper Egypt bad a negative effect on the crop pecductivIly by 1.19 tonifeddan. Also at south Sinal the effect ol the temperature In luly Is considered as anon parameter on the tomato yield, Minh decreased by 1.53 ton. For potato crop the study reveakd that in February when temperature bloused the pnattuctivny of potato crop increased by 0.48 ton/leddan, at Upper Egypt, Moreover, temperatures in gamine and Mardi were neeebve parameters that Increased the total produotion of potato crop by 0.61 and 0.74 tones, respective, at North Sinai. But the Increase of temperature during March at northern Deb caused a yield decease by 0.73 ton per redden. For the Cucumber crop, the study showed the increase Cl temperature to March at the Northern Delta, in February at the Southern Delta and Middle Egypt, In March at the North Simi and in Febtuary at Matrouh, the odd or cucumber Increased by 0.27, 0.22, 0.34, and 0.47 tonsifecklan, respectively. However at Southern Delta and Midc•e Egypt, the Incase 'temperature in May, mused a pecduclivIty decease by 0.50 ton per fecktan.