A Scramjet is a supersonic combustoin ramjet engine which involves supersonic combustion at high pressures through the formation of a shock train. As the air passes through the inlet it gives pressure rise to shock waves which can lead to boundary layer separation. Shock boundary layer interaction (SBLI) has a detrimental effect on the performance of the scramjet as it can lead to the formation of normal shocks. Velocity will decrease to subsonic levels which leads to engine un-starting and may ultimately cause catastrophic consequences for the engine or may even lead to the failure of flight controls. There are various methods that have been proposed to control and suppress SBLI. One of those methods is boundary layer bleed which has been studied here. Boundary layer bleed can reduce the amount of the flow separation that occurs in a normal scramjet inlet at the point of separation by means of suction or tangential blowing and can enhance its performance. A 2D CFD analysis has been performed on Ansys Fluent 15.0 to study the effect of the boundary layer bleed by means of suction on various performance parameters like the Static pressure, stagnation pressure recovery and flow distortion. This is then compared with the results obtained in models without boundary layer bleed at inlet conditions of Mach Number 3.2 and Static Pressure 12350 Pa using the SST Turbulence model in Fluent on Scramjet inlet models having both 0 and 5 cowl angles geometries. The same comparison is also done on models where the inlet is forcefully un-started by increasing back pressure . The bleed size was limited to 20% of the mass defect as the effect of the bleed on the mass flow rate entering the scramjet inlet also needed to be determined. It was observed through simulations that boundary layer bleed causes a reduction in separation bubble length and the separation bubble height while improving all the performance parameters mentioned above at the expense of the mass flow rate entering the scramjet inlet. © 2016 International Science Press.