Technical Abstract: During the last decade, there has been a continuous rise in consumption of fresh easy-to-peel mandarins. However, mandarins are much more perishable than other citrus fruit, mainly due to rapid deterioration in sensory acceptability after harvest. In the current review, we discuss the biochemical components involved in forming the unique flavor of mandarins, and how postharvest storage operations influence taste and aroma and consequently consumer sensory acceptability. What we perceive as mandarin flavor is actually the combination of basic taste, aroma and mouth-feel. The taste of mandarins is principally governed by the levels of sugars and acids in the juice sacs and the relative ratios among them, whereas the aroma of mandarins is derived from a mixture of different aroma volatiles, including alcohols, aldehydes, ketones, terpenes/hydrocarbons, esters and others. During postharvest storage and marketing, a gradual decrease in mandarin sensory acceptability can occur, which has been attributed to decreases in acidity and typical mandarin flavor and accumulation of off-flavors. Biochemical analysis of volatile and non-volatile constituents in mandarin juice demonstrated that these changes in sensory acceptability were concomitant with decreases in acidity and contents of terpenes and aldehydes which provide green, piney and citrus aroma in the one hand, and increases in ethanol fermentation metabolism products and esters, on the other hand, that are likely to provide “overripe” and off flavors. Overall, we demonstrate the vast importance of the genetic background, maturity stage at harvest, commercial postharvest operation treatments, including curing, degreening and waxing, and storage duration on mandarin sensory quality.