Abstract: This paper discusses a method of determining GPS carrier phase ambiguity in kinematic environments.Mathmactical model is set up.After searching space is defined,all ambiguity combinations are tested with statistic check epoch by epoch until the only correct one is found.Simultaneously accumulated sum of squares of residuals of every ambiguity combination is calculated which can be used to distinguish the correct ambiguity set from the wrong sets easily.Finally simulations are performed which show this algorithm is effective.