The invention relates to an anti-bending multimode fiber and manufacturing method thereof. The fiber comprises a core and a cladding and is characterized in that the radius of core R1 is 24-26 microns, refractive index section of the core is like a parabola, refractivity maximum delta1 is 0.9-1.1%, the cladding outside the core is composed of three parts, the radius of inner cladding R2 is 1.04-1.6 times of the radius of core R1, delta2 is minus 0.01-0.01%, intermediate cladding is gradually changed in refractive index, the radius of intermediate cladding R3 is 1.06-1.8 times of R1, refractivity is gradually changed into delta4 from delta2, the radius of outer cladding R4 is 2.38-2.63 times of R1, and delta4 is minus 0.20% to minus 0.40%. The invention reduces fiber bending additional attenuation and improves anti-bending performance of fiber but also basically eliminates inner stress of fiber, greatly improves mechanical properties of fiber, and service life of fiber operating in minor radius for a long time also can be guaranteed. The manufacturing method of the invention is simple, convenient and effective and is applicable to mass production.