Baffles enhance heat transfer by disturbing boundary layer and bulk flow, creating impingement cooling, and increasing heat transfer surface area This study was conducted to determine how a single baffle placed at the inlet of a rectangular channel affects heat transfer and friction characteristics. The baffle was mounted on the upper inner surface of the channel, and the channel base was heated by constant heat flux. Two different clearance ratios (C/H=0.6, 1) and four baffle inclination angles were used (30, 45, 60, and 90°). Reynolds number changed in the range of 7100-28500. It was found that the heat transfer and friction factor depend significantly on the baffle inclination angle, clearance ratio, and Reynolds number. The average Nusselt number and friction factor increased with the decreasing clearance ratio and the increasing baffle angle The performance analysis by the equal friction factor criterion showed that the use of the inlet baffle is not themiodynamically advantageous on the basis of heat transfer enhancement.