On the basis of the experiments of cement-soil strength and the strain determination under unconfined compression for the cement-soil samples which laying four different strain test blocks, sets up the relations between the cement-soil stress and the test block strain at a lateral restraint stress, and obtains the stress test method of cement-soil piles. The results of comparative tests show that: the test block of PVC pipe has a minimum deviation and is low sensitive to the cement-soil age, the strain of age 7 days and that of 28 days are closer with the increment of the cement-soil stress, and it can be applied to the stress test of cement-soil piles.