Volatile aromatic components produced during the brewing process of red raspberry vinegar were separated and identified by headspace-solid-phase microextraction-gas chromatography-mass spectrometry (HS-SPME-GC-MS). This was combined with the odor threshold value to determine the relative odor activity value at different brewing stages. Principal Component Analysis (PCA) was then applied to evaluate the contribution of aromatic components to the overall flavor of raspberry vinegar in order to determine the key flavor of raspberry vinegar. Four key flavor compounds in red raspberry juice–β-ionone, damascenone, D-limonene, and naphthalene, were found. After the alcohol fermentation stage, β-ionone and ethyl acetate were the two key flavor compounds produced. After the acetic acid fermentation stage, β-ionone and α-ionone were the two key flavor compounds. After the aging stage, β-ionone, ethyl acetate, and α-ionone were the three key flavor compounds. PCA showed that PC1 reflected the important role of microbial fermentation and aging in the formation of the overall flavor in red raspberry vinegar. PC2 showed that the aromatic compounds and carbonyl compounds changed significantly during the formation of flavor in red raspberry fruit vinegar.