The problem of viscous flow & heat transfer over a 2-D steady free convection boundary layer from a vertical surface is studied taking into account slip boundary conditions & exponential decay internal heat generation on variation of fluid viscosity with temperature. The governing equations of the problem are steady reduced to couple non-linear moment & the energy equation to be similar by introducing suitable similarity transformation. Dimensionless velocity and temperature profiles are presented graphically for various values of Prandtl number()Pr, velocity slip parameter ()a & temperature slip parameter ()b with & without internal heat generation. Velocity gradient & temperature gradient are also discussed & are given in tables