Impingement heat transfer is one of the useful cooling methods for high temperature gas turbine blades and/or guide vanes in aeroengines.After the cooling jet impinges on the leading edge of the turbine blade and/or guide vane,it flows downstream and turns to be the initial crossflow for the aft row of impinging jet.The process of impingement heat transfer is quite complicated, especially when the target surface is rib roughened. In this paper,impingement fluid characteristics from rib roughened surface with two dimensional arrays of circular jet with initial crossflow have been investigated experimentally.Through thousands of experimental data,the effect of several flow parameters ( Re j=7000~15000,G c/G j =0~0.5) and geometric parameters ( Xn=5~15,Zn=1 5~5,p/e=5~12,e/d =0 5~1 5) on fluid characteristics has been studied.It would be useful for the design in gas turbine hot section.