According to genetic algorithm (GA) has the advantage to resolve the global numerical value optimization problems in robust and parallel way, the adaptive genetic algorithm(AGA) is applied to resolve the single frequency GNSS carrier phase integer ambiguity in this paper. The fitness function based on the non-linear integer weighted Least-square principle is constructed, while the baseline length is to determine the integer ambiguities search range as the constraint. Finally the adaptive genetic algorithm (AGA) is applied to resolve the integer ambiguity. Simulation numerical results show that the resolution with adaptive genetic algorithm is more robust and reliable than simple genetic algorithm (SGA).