Abstract: Many indexes have been investigated in the research from exterior appearance to yield character of radish. After the filtration of those indexes, Four-heat tolerance index was put forward: fresh weight unit area of seedling, heat injury index, death rate of plant in summer, and effective root rate. Identification standard as follows: It is strong heat tolerance material if its fresh weight unit area in the seeding period(W/A)≥0.5g/cm2, middling heat tolerance material (W/A)for 0.2g/cm2-0.5g/cm2, feel heat material (W/A) for≤0.2g/cm2. Leaf heat injury index ≤10% is strong heat tolerance material, the heat injury index is 10%-30% belong to middling heat tolerance material, the heat injury index ≥30% is feel heat material. Death rate of plant in summer≤10% is strong heat tolerance material, 10%-20% is middling heat tolerance material, ≥20% is feel heat material. Effective root rate≥90% is strong heat tolerance material, 80%-90% is middling heat tolerance material, ≤80% is feel heat material. Death rate of plant in summer and effective root rate are two simple indexes of identification in the field, so it is extensive used for the first identification screening of large materials.