The present invention relates to a signal combining apparatus of the active phase array antenna. The signal combining apparatus includes a plurality of signal distributors for receiving a signal from an antenna array element located at boundary between sub antenna arrays and distributing the signal to the sub antenna arrays, which include the antenna array element; and a plurality of signal combiners for combining the signal from a plurality of antenna elements and the signal distributors in corresponding sub antenna array. The present invention can prevent degrade a performance caused by sudden phase difference and can effectively receive tracing signal by passing a signal of antenna element located at boundary between sub arrays antenna to both signal combiners corresponding to both of sub antenna arrays.
