Abstract: Aimed at the soil fertility obstacles generally existing in mountainous region orchard in Chongqing, and the issues of reprocessing of waste products from agricultural production and processing, using biomass resources as research subject, by the means of biomass char and organic matter (straw, fungus residue) carbon sinks, this test studied the effect of different carbon sequestration pathway on citrus orchard’s soil fertility and citrus fruit quality. The results showed that each treatment reduced the citrus soil’s pH value and bulk density, increased organic matter and total potassium content in the citrus soil, as well as the total potassium content in the citrus leaves, but there was no regular change in total nitrogen or total phosphorus in citrus soil and leaves. Among them, when each citrus tree was applied with 6 kg fungus residue, soil bulk density decreased to 1.48 g/cm³, reaching a significant level; when each citrus tree was applied with 3 kg stalks, soil organic matter increased to 36.47 g/kg, while total potassium content increased to 9.68 g/kg, both reaching a significant level. Besides, it could improve citrus soluble solids, reduce total acid content in the fruit, improve fruit solid acid ratio, and promote citrus fruit rich flavor.