The invention provides a molecule particularity mark primer of mushroom Cr02 strain and a method for to distinguishing and detecting the mushroom Cr02 strain by using the primer. The sequence of the primer is: an upstream primer is 5'-TCTCGATGCAAGAAACTTGAA-3', a downstream primer is 5'-TCGGTCAAAATTAGTCAGGT-3'. The invention has the main advantages that compared with conventional morphological detection, antagonism and fruiting experiment, the method has short detection time and high accuracy; the method only needs 1-3 days for detection, while the conventional antagonism needs at least two weeds for detection, and the fruiting experiment needs at least 3 months for detection.