The invention relates to a dual-polarized oblique beam 
waveguide slot array antenna. The dual-polarized oblique beam 
waveguide slot array antenna comprises more than one unit array antenna; the unit array antenna is formed by a horizontally polarized 
linear array and a vertically polarized 
linear array; the horizontally polarized 
linear array and the vertically polarized linear array are arranged in a horizontal staggered mode; the horizontally polarized linear array is arranged on the upper layer; the vertically polarized linear array is arranged on the lower layer; a horizontally polarized single 
ridge waveguide is provided with a broadside V-shaped 
radiation slot; a vertically polarized single 
ridge waveguide is provided with a broadside U-shaped 
radiation slot; a feed portion is in a 
ridge waveguide form and accordingly the integral bandwidth of the antenna is effectively guaranteed, the antenna achieves beam inclination, meanwhile the matching bandwidth of the antenna and the 
radiation efficiency are guaranteed. The integral antenna can achieve a good 
circular polarization axial ratio characteristic and meanwhile achieve a 45-degree 
fixed beam inclination angle due to appropriate 
phase compensation of a 
feed network. Compared with the waveguide 
slot antenna at the same 
frequency band, the dual-polarized oblique beam waveguide slot array antenna is small in size, low in profile and effectively reduces costs due to a bolt fastening installation mode.