Abstract: A concept of new design is suggested by use of in situ cement soil strength after considering the present quality problem of deep cement mixing piles resulted from the high strength of cement soil mixed in laboratory and very low strength of cement soil mixed in situ, so the discrepancy of laboratory cement soil strength and in situ construction quality can be avoided in the design. Then, the several methods of settlement calculation of deep cement mixing piles are discussed, especially the problem of arbitrary factor in the deep massive foundation model.The reasonable methods of settlement calculation for deep cement mixing piles are suggested.