The morning glory spillways is a type of spillways used to pass the flood from upper to lower height. These types of spillways are used in dam reservoir of narrow valleys and locations where the slope of reservoir walls is high. In morning glory spillways, the existence of whirlpool could reduce flow rate, flow rate index and spillway function. The zigzag spillway is introduced as a proper option for compensating the problem which spillways face in passing maximum possible flow rate. These spillways have non-linear crown and in a definite width, compared with spillways with straight crown of similar height, the flow rate passing through the spillway is direct. In the present study, a physical model of morning glory spillway is developed and an entrance to the spillway and zigzag spillways is installed. In different parts of spillway and for different flow rate, the flow rate index is examined in free flow state and the results are offered in diagrams. The analysis of experimental data shows that in a fixed submergence depth, the increase in length of spillway and number of zigzag will increase the flow rate.