Abstract: Uplift piles, as one type of deep foundation, have been widely used in various field. But because of lack of a solid theoretical foundation, the value of the ratio of ultimate shaft capability in tension and compression are mainly based on empirical data. Limit equilibrium equations of single pile are established when vertical compressive loading test and self-balance measurement method are carried out. Furthermore, a simple formula, taking into consideration the diameter of piles and the soil properties, is derived to caculate this ratio. Reasonable agreement has been observed between the measured and predicted values of ultimate uplift capacities of piles beared in the strata with better consolidation status.