Several investigators have conducted studies on local scouring around or downstream of hydraulic structures. The objectives of these studies were the maximum scouring depth and bed erosion pattern in channels and rivers. Due to the complexity, this phenomena has been mostly studied using model experimentation rather than numerical/analytical modeling. Transition from super- to subcritical flow downstream of the hydraulic structures, including weirs, spillways, gates, culverts and etc. accompanies by hydraulic jump associated with expansion, turbulence, water circulation and local head loss thereby eroding the bed materials. Since the head loss in preferred to be forbidden in irrigation and drainage systems, therefore in not the main concern of the design engineers who instead prefer to exclude the hydraulic jump from super- to subcritical flow regime due to unfavorable flow conditions. Recently experimental and analytical studies have been performed on the flow transition from super- to subcritical flow regime without a hydraulic jump. However, there is lack of detailed information about the interaction between the fluid flow and sedimentation downstream of the transition structure. In the present study, scouring of uniform bed materials downstream of the transition from super- to subcritical flow was investigated. Experiments were carried out in a 9.5m long, 0.4m wide and 0.7m high flume in the laboratory of hydraulics at the department of civil engineering, Isfahan University of Technology. Experiments were performed with different values of discharges and approach flow depths. The upstream approach flow Froude number varied between 2.05 and 2.85. The scouring equilibrium depth and the profiles of erosion were measured at regular time intervals. Results show particular geometrical similarity among the time history variation of scouring hols. The main characteristics of the scouring holes including the maximum scouring depth, length of the hole and the height of the dunes were found to be increased by increasing the upstream approach flow depth and velocity and densimetric Froude number. Based on dimensional analysis and applying regression analysis, an empirical equation was achieved for estimating the maximum equilibrium scouring depth. It was shown that the eroded bed is almost symmetrical in respect to the centerline of the flume. The maximum scouring depth usually occurs besides side walls of the flume. However, two lateral cavities were also observed. Furthermore, experiments were performed on scouring through and downstream of the hydraulic jumps. Latter results were compared with those downstream of the transition structure. The dimensions of the eroded region decreased significantly by excluding the hydraulic jump during the transition from super- to subcritical flow if compared to the scouring through a hydraulic jump. Close agreement between the results of scouring hole were obtained while the densimetric Froude number increases for both cases of with and without the hydraulic jump. Key words: Excluding the hydraulic, Hydraulic jump, Scouring, Subcritical flow, Supercritical flow, Transition.