In this paper, performance simulation of a hybrid diffuser, hybrid diffuser with suction and hybrid diffuser with fence have been carried out. The two-dimensional steady differential equations for conservation of mass and momentum have been solved for the Reynolds number ranging from 100 to 600. During the simulation, a fixed aspect ratio of 2 and a fixed value of half divergence angle of 3.5° have been considered for all the diffuser geometries. At the inlet, fully developed velocity profile has been used. The effect of Reynolds number on average static pressure have been studied in detail, and compared between three diffuser geometries. The effective diffuser lengths for achieving maximum average static pressure at the diffuser exit have been computed for the considered Reynolds numbers.