The invention discloses a broadband reflecting array compact field device with large angle off-axis and small angle offset functions. The device mainly comprises a reflecting array aperture and a feedsource. According to the method, a front unit aligns and corrects spherical wave emitted by the feed source into quiet zone plane-wave field for large angle off-axis outgoing; and the feed source adopts a quasi paraxial structure for offset of illumination reflecting array at small angle, so that front residual mirror wave beam is far from a quiet zone to improve the plane wave quality. In the design, an alternating projection algorithm in combination with a bear-field plane wave spectrum transmission technology rapidly synthesizes reflecting array aperture phase stimulation required by the optimum quiet zone. The device is lower in requirement on the machining precision of a reflecting array antenna than that of the traditional reflecting surface, the reflecting array aperture adopts a printed circuit structure, the technology is simple, the structure is light, a feed source broadband is tuned and matched to realize aperture collimation, and the device is applied to broadband millimeter wave/submillimeter wave compact field systems at low cost.