The invention discloses a high-strength unequal helical angle end mill, which includes a cutting part and a handle part, the whole cutting part is provided with a plurality of chip discharge grooves helically extending from a bottom end to the handle part, a surface of each chip discharge groove towards a cutting rotation direction is a front knife face crossed with a peripheral face of the cutting part to form a peripheral blade, the helical angle of at least one peripheral blade is different from that of other peripheral blades, a face of the peripheral faces of the cutting part connected with the peripheral blade is a first rear knife face, and a face connected with the first rear knife face is a second knife face, a total length of the cutting part is Ap, the first rear knife face extends from the bottom end of the cutting part to the handle part, and the second rear knife face at least extends from the bottom end of the cutting part to a site Ap/3 away from the handle part. The high-strength unequal helical angle end mill has the advantages of integral improvement on strength of each peripheral blade, high cutting efficiency, and long service life.