The mechanical properties of coconut shell aggregate concrete (CSAC) namely splitting tensile strength, impact strength have been determined and a comparison is made with conventional granite aggregate concrete (CGAC) in the 30 days short-term experimental investigation. From the test results it is observed that coconut shell aggregate concrete has considerably sufficient strength. But the splitting tensile strength of coconut shell aggregate concrete is 50 % less than that of conventional granite aggregate concrete. The coconut shell aggregate concrete results are lies within the limits of structural lightweight concrete. Hence it is considered as structural light weight aggregate concrete. The impact strength result of coconut shell aggregate concrete CSAC is less than the conventional granite aggregate concrete CGAC.