This study was carried out on the roof of the Thermal Eng. Laboratory, Mechanical power Dept., Fac. of Eng., Mansoura Univ., during selected clear days of April and one clear day of May, 2013. An experimental set up was designed and installed to measure the absorptance of 11 coated surfaces and one sheet without color. Then, the temperature of tested surfaces were calculated. The results showed that, G.I sheets coated with black bored (Bb), polish black (Pb), brown (Br), red (R), violet (V),

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... en (G), blue (Blu), G.I. sheet without color, dark yellow (Yd), yellow (Y), silver (S) and white (W), are 0. 92, 0.886, 0.888, 0.855, 0.852, 0.843, 0.830, 0.802, 0.788,0.785, 0.746, and 0.666 respectively. A liner equation was derived to predict the absorptance (α) of these colored oil painted surfaces basing upon their temperature (T) as follows: R²=0.996 This equation may be applied at agricultural field to select the surface coating colors of buildings, greenhouses, soil mulching poly ethylene sheets and absorbers (solar collectors).