Flower fragrance is a significant ornamental feature of ornamental plants. As a worldwide woody flower， Rhododendron is famous because of rich colors and diverse patterns. Its floral fragrance is an important indicator of its quality. Studies have demonstrated that terpenoids， alcohols， esters， and ketones are the main components of rhododendron florets， and the release of these compounds is influenced by flower development， release site， and environmental conditions. Terpenoids are the most important floral components of Rhododendron， and terpenoid synthase gene is the main regulator in the metabolic pathway of floral substances. Through the genomics and metabolomics study， TPS family genes of Rhododendron ovatum were much more than those of other odorless Rhododendron plants. It is of great significance to study the floral composition and biosynthesis pathway in different species and varieties of Rhododendron for aromatic breeding and comprehensive utilization. This study reviewed the determination and analysis methods of floral composition of Rhododendron plants， the aroma components of Rhododendron species in subgenera， the synthesis and release law of aroma， and the biosynthetic pathway of aroma and key genes， which provided reference for the study of the genetic law of the synthesis and metabolism of main floral substances and breeding new varieties with obvious characteristic fragrance in Rhododendron.