The invention relates to a direct turning and roughing method for an optical collecting lens of an extreme ultra-violet lithography light source, relates to a roughing method for an optical collecting lens, and aims to solve the problem that when an optical collecting lens of an extreme ultra-violet light source if processed by the copying method, a solid shaft fitting the face of the required collecting lens is required to be processed first, then nickel deposition is performed on the surface of the solid shaft, the nickel shell is stripped out to form a base of the collecting lens, according to the technical scheme, the requirements on accuracy control during processing are very stringent, and processing cost is increased. The direct turning and roughing method for the optical collecting lens of the extreme ultra-violet lithography light source includes firstly, rough turning blank, namely rough turning aluminum alloy into a cylindrical workpiece by the aid of an ordinary lathe; and secondly, numerical-control turning, namely turning the cylindrical workpiece by the aid of a numerical-control lathe according to the face of the collecting lens. The method is applied to direct turning and roughing of the optical collecting lens of the extreme ultra-violet light source.