Abstract:The purpose of this study was to investigate the effect of ozone treatment on the relationship between postharvest decay and cell wall metabolism of Hami melon."Xizhoumi 25"Hami melon was treated with ozone at 0 mg/m3（control group）and 10 mg/m3（ozone treatment group）for 4 h and then stored at a normal temperature of（22.0±0.5）℃.Then the decay symptoms were observed，and the decay index，decay rate，and indicators related to cell wall metabolism were measured.The results showed that compared with the results in the control group，ozone treatment reduced fruit decay index，decay rate，and decay symptoms，inhibit the activities of polygalacturonase（PG），β-glucosidase（β-Glu），β-galactosidase（β-Gal），and decrease the activity of cellulase（Cx），thereby delaying the degradation of protopectin and increase in soluble pectin content，better maintaining the harness of Hami melon fruit，delaying fruit softening，reducing fruit rot，and prolonging fruit storage period.Therefore，the findings revealed that ozone could inhibit the degradation of pectin by cell wall degrading enzymes to maintain cell wall strength and delay the softening and fruit decay.