In order to breed a new P. eryngii cultivar with high temperature tolerance trait to cope with climate change, strainsand cultivars were characterized at 20^oC that is 5^oC higher than normal condition followed by screening for the characteristicssuch as required days to harvest, quality and yield. Monokaryons from the selected strains were crossed. Da-32×KNR2322-15derived from the crosses between KNR2322 having characteristics of short growing day and Da(Ga5Na5-4×KNR2312-7) havingcharateristics of high guality and yield at 20^oC, showed 14.9 days for harvest, 120.6 g yield, and 7.0 quality in the first trial. Thestrains were named as Taeyangsongi and cultivated on a large scale to compare with Kenneutari No. 2 at a mushroom farm. Yieldof Taeyangsongi (109 g) was significantly different(P=0.001) from Kenneutari No.2. Quality of the new (6.6) and the referencecultivar (3.5) was also statistically different (P=0.001) The brightness of pileus of Taeyangsongi (59.5) was 10 points less than thereference cultivar due to which it has an inability to bear high temperature stress. Thus, PCR reactions with URP2 discriminatedbetween Taeyansongi and reference cultivars (Keneutari No. 2 and Aeryni).