Known as a “super grain”, quinoa is the only single plant that meets all nutritional needs of the human body. Aroma is the key factor determining the flavor quality of quinoa, and its core lies in the composition characteristics and dynamic changes of aroma substances. Previous studies have shown that the characteristic aroma components of quinoa include aldehydes, alcohols, ketones, esters and heterocyclic compounds, and the aroma of quinoa is significantly affected by processing methods (puffing, frying, roasting, cooking, microwave treatment, fermentation and vacuum freeze-drying). While many studies have been published on the aroma components of quinoa and the effect of processing on quinoa aroma, the formation mechanism of quinoa characteristic aroma and the mechanism of processing affecting quinoa characteristic aroma need to be further explored. Therefore, this paper systematically reviews the aroma characteristics of quinoa and summarizes recent studies on the effects of different processing methods on the characteristic aroma of quinoa and its formation mechanism. The purpose of this review is to provide a reference for in-depth research on quinoa flavor in order to promote the high-quality development of the quinoa industry.