This article investigates the film cooling effectiveness and heat transfer in three regimes for a film-cooled gas turbine blade at the leading edge of the blade with 45 0 angle of injection. A Rolls Royce blade has been used in this study as a solid body with the blade cross section from Hub to Shroud varying with a degree of skewness. A 3-D finite-volume method has been employed (FLUENT 6.3) with a   k turbulence model. The numerical results show the effectiveness cooling and heat transfer behavior with increasing injection blowing ratio BR (1, 1.5 and 2). In terms of the film cooling performance, high BR enhances effectiveness cooling on pressure side and extends the protected area along the spanwise direction from hub to shroud. The influence of increased blade film cooling can be assessed via the values of Nusselt number in terms of reduced heat transfer to the blade.