The invention discloses a method for identifying a milk production character of dairy cattle based on a CDKN1A gene and an application thereof. The method for identifying the milk production character of dairy cattle disclosed by the invention is used for detecting the genotype substance of No. 10565335-locus deoxyribonucleoside on 23# chromosome of cattle genome. A test proves that the method disclosed by the invention is simple, convenient, quick and sensitive; the result is reliable, stable and accurate; the method can be used for assisting in identifying the cattle group with excellent milk production character and meets the requirement for large group size detection of laboratory; the method can be used for early screening the to-be-selected cattle, can reduce the breeding cost, can effectively increase the milk yield of the cattle in practical production and can play a great role in the cattle-breeding work.