The experiment on Yield Potential Comparison on S/2 d3 and S/2d4 Tapping Systems of Clones IRCA230 were practiced on farm research at Chup Rubber Research Station of Cambodian Rubber Research Institute (CRRI). The experimental design was the RCBD with 8 treatments and 4 replications with a total number 400 trees per replication. They were opened at the standard girth of 50 cm measured at 1m high. All the trees were opened at 1.3 m from the ground. The tapping systems were S/2 d3 7d/7 and S/2 d4 7d/7. This clonal typology is based on measurements issued from the latex diagnosis. The objective of the experiment was to investigate the yield potential comparison of the tapping system S/2 d3 7d/7 and S/2 d4 7d/7 based on frequency of ethephon stimulation. Stimulation was related to the sucrose and inorganic phosphorus contents of the latex cells. Clone IRCA 230, with higher sugar content, with high ethephon stimulations per year obtained the highest yield. The cumulative yield in gram per tree over 8 years of tapping showed frequency d3 higher yield than frequency d4. The yield of tapping frequency with stimulation 1.5% 7/y control was higher than them.