Abstract: Abstract: 【Objective】It is meaningful to study reciprocity on melon and garlic for relaxing the problem of soil sickness.【Method】contents of chlorophyll and parameters photosynthesis and chlorophyll fluorescence of melon ‘Jinmi’ leaves were measured after planting 30 days. Pot experiment of non-continuous cropping and continuous cropping soil was conducted by using garlic root aqueous extracts treatment. 【Result】The results showed that continuous cropping decreased content of chlorophyll and carotenoid, net photosynthesis rate (Pn), stomatal conductance(Gs),intracellular CO2 concentration and transpiration rate(Tr). Continuous cropping increased original fluorescence intensity(Fo),but deceased maximum photochemical efficiency (Fv/Fm), actual photochemistry efficiency of PSII (ΦPSⅡ), photochemical quenching (qP) of the melon leaves. After treatment of garlic root aqueous extracts, contents of chlorophyll and carotenoid, Pn, Gs, Ci, Tr, Fv/Fm, ΦPSⅡand qP of the melon leaves were increased,while Fo decreased both continuous cropping and non-continuous cropping. 【Conclusion】Melon is a crop that it is not fit for continuous cropping. Garlic root aqueous extracts can promote melon growth and relax the problem of soil sickness.