Protection of the coasts against the wave damages is a topic of widespread interest among the researchers and marine engineers. One of the methods to protect the coasts is implementation of the breakwaters or submerged obstacles. Breakwaters dissipate a great part of wave’s energy by inducing the turbulent currents. In the present research, effects of the height and relative distance of two rectangular barriers on the flow field and free surface profile, in case of a solitary wave passing above them, by both experimental and numerical methods. In the experimental procedure, white light scanning technique is used to investigate the free surface profile and identify the wave height and PIV technique is implemented in order to study the flow field and the created vortexes. In order to do so, 2 upright placed barriers with rectangular cross section of 12 cm height and 8 cm lenght, and 30 cm width in canal’s path direction are installed in relative distances of 4, 8, and 16 centimeters in a 6 m length water canal with a height of 0.6 m and a width of 0.3 m. Then the aforementioned parameters are measured for a solitary wave passing above the barriers. A piston-type wave maker is used in order to create the solitary wave. In the numerical procedure, simulations are done in the ANSYS Fluent software by using the finite volume method and volume of fluid multiphase model. Laminar flow model and two turbulence models k-? and LES, were investigated and their results are compared with experimental results. The results of this comparison indicate that the results of the laminar flow and LES model are consistent with the experimental results. Results show that while increasing the relative distance between the barriers, the wave height declination increases for distances up to 12 cm and decreases for higher distances up to 20 cm. Moreover, as a result of the barriers being close to the water surface, the solitary wave breaks when passing the barriers and the magnitude of this break increases as the barriers relative distance is extended. The aforementioned wave break and resulting water flux into the canal create a counter-clockwise vortex behind the second barrier. Study of the drag coefficient showed that as the barrier heights are raised, the drag coefficient on the two barriers demonstrate an increase. This coefficient reaches its maximum value as the wave approaches the barrier, then decreases after the wave passes the barriers, and in some cases reaches negative values, and finally approaches zero. Also the presence of a second barrier causes the drag coefficient to arrive at the first barrier to negative values. Keywords: Solitary Wave, Vortex, White Light technique, PIV technique