Global position system (GPS) adaptive array antenna forms null beam to suppress the interference in order to communicate normally. The nulling beamforming model is actually an optimization technique. Because the traditional adaptive algorithms usually obtain the partial optimum solution, in this letter, we propose adaptive ant colony algorithm (AACA) can find the desired solution which is a global search method. The article explains AACA and it can work well in the complex number space. Some examples demonstrate the availability of this algorithm.