In this paper, an integrated decoupling structure is proposed for millimeter wave dual-polarized array antenna with TM&TE coupling. Based on the TM&TE integrated decoupling principle, a slot-array defected ground structure (DGS) is designed, which can realize the simultaneous decoupling of two polarizations of the millimeter wave dual-polarized array antenna. The operating frequency of the antenna is 24 GHz and the spacing between antenna elements is 0.4 wavelength. The simulation results show that TM coupling and TE coupling are decreased by about 16dB and 12dB respectively, which indicates that the proposed slot-array DGS can realize TE&TM integrated decoupling simultaneously. Furthermore, the co-polarization isolation and cross-polarization isolation are improved by about 15 dB and 9 dB respectively.