Housekeeping genes are important for measuring the transcription expression of functional genes; 10 traditional reference genes,TUB, TUA, GADPH, EF1, 18S, GTP, ACT, UBI, UBC,andH2A, were tested for their adequacy inLentinula edodes(L. edodes). Using specific primers, mRNA levels of these candidate housekeeping genes were evaluated in mycelia ofL. edodes, which were treated with high-temperature stress at 37°C for 0, 4, 8, 12, 18, and 24 hours. After treatment, expression stability of candidate genes was evaluated using three statistical software programs: geNorm, NormFinder, and BestKeeper. According to geNorm,TUBhad the lowest M values inL. edodesstrains 18 and 18N44. Using NormFinder, the best candidate reference gene in strain 18 wasTUB(0.030), and the best candidate reference gene in strain 18N44 wasUBI(0.047). In BestKeeper analysis, the standard deviation (SD) values ofUBC,TUA,H2A,EF1,ACT,18S, andGTPin strain 18 and those ofGADPHandGTPin strain 18N44 were greater than 1; thus, these genes were disqualified as reference genes. Taken together, onlyUBIandTUBwere found to be desirable reference genes by BestKeeper software. Based on the results of three software analyses,TUBwas the most stable gene under all conditions and was verified as an appropriate reference gene for quantitative real-time polymerase chain reaction inL. edodesmycelia under high-temperature stress.