Method for breeding improved mutton sheep strain

The invention provides a method for breeding an improved mutton sheep strain, which includes the steps: firstly, using a plurality of rams as strain ancestors to mate with 30-50 ewes respectively so as to establish a plurality of families; secondly, performing beneficial-trait within-family selection to more than four generations of the families established in the step 1; thirdly, subjecting the families selected in the step 2 to family hybridization; fourthly, using hybrids obtained in the step 3 and family non-hybrids to establish a strain breeding core group, and grouping other individualsas a production group; fifthly, subjecting the core group established in the step 4 to beneficial trait selection, opening the core group, allowing selected qualified individuals in the production group to enter the core group, introducing 'foreign blood' timely to avoid inbreeding depression; and sixthly, obtaining the mutton sheep strain with beneficial traits adaptable to local environment by multi-generational breeding. By using the method to breed the improved mutton sheep strain, dependence on foreign varieties is lessened, and the current situation of 'all introduction and propagation and no breeding' in the field of breeding sheep introduction in China is changed.