Pectin is widely used as a health food colloid with its demand growth for years. Recovery of pectin from the process water of mandarin canning is the important new way for pectin production. The different parameters in canning process， such as fruit size classification， acidic and alkaline process for segment membrane removal， will affect the following recovered pectin. Thus， pectin extraction from mandarin segment membrane with three fruit sizes （diameter of 7.3-7.7， 5.9-6.3 cm and 5.0-5.4 cm）， under three extraction processes， that is， high temperature acidic extraction （commercial pectin process）， low temperature acidic extraction （mandarin canning acidic process）， and low temperature alkaline extraction （mandarin canning alkaline process） were conducted. The results show that the extraction methods significantly affect pectin properties. Low-temperature alkaline extraction pectin has the highest of neutral sugar content and molecular weight， while high temperature acidic extraction pectin ranks the lowest of the above indexes. The fruit size has a small influence on the pectin. Large mandarin contains less acid soluble pectin and more alkali soluble pectin comparing to the small mandarin. In addition， the molecular weight of large mandarin pectin is smaller. Thus， extraction method and mandarin raw material differences will affect the properties of pectin. This work provides an important knowledge for pectin extraction.