To investigate the effects of lemongrass essential oil on the key volatile aroma compounds of pickled radish (PR) during storage, this study used headspace–gas chromatography–ion mobility spectrometry, fingerprint analysis, multivariate statistical analysis, and molecular docking to study different PR samples. The results indicated that a total of 48 volatile aromatic compounds were identified. Fingerprint analysis revealed that the aroma profiles of samples at different storage stages were different. Using the screening criteria of p < 0.05 and variable importance for the projection > 1 in multivariate statistical analysis, and relative odor activity value > 1, six potential key aroma compounds were selected. Furthermore, phenylethyl acetate, β-ocimene, 4-heptanone, and limonene were determined as the key aroma compounds that affect the PR aroma profile after adding lemongrass essential oil. Moreover, the addition of lemongrass essential oil increased the fruit and sweet aroma of PR samples during storage. The results of molecular docking indicated that the recognition of these four odors was mainly accomplished through hydrophobic interactions and hydrogen bond interactions by docking OR1A1 and OR5M3 receptors. This study can offer a preliminary foundation and theoretical support for the in-depth exploration of the paocai industry.