In this research, the experimental works were conducted to study the lap strength of the headed reinforcements placed in a horizontal single layer. Ten lap splice specimens were tested. Wide beam specimens were fabricated with a lap splice at mid-span. They were loaded in flexure, placing the lap splice in tension. The variables in this study were: lap length(6~16 times the diameter of reinforcement), diameter of reinforcement(D19, D25), and debonded versus bonded bars. Specimens were instrumented to measure the load on the specimen, strain along the reinforcements within the lap zone, and mid-span deflection. The cracking behavior was also observed and recorded. The following conclusions were drawn from the test results in this study; 1) The initial crack of the specimens lapped developed at the heads of reinforcements. The specimens failed by the crack with the struts acting between the opposing heads of lapped reinforcements. 2) Bond contribution to increase strength and deformation was great. In accordance with the this result, it is necessary to consider the bond strength for the lap length design of headed reinforcements. 3) CCD method evaluated the maximum strength as 2.21~4.96 times the test maximum strength.