Abstract: Using headspace solid-phase microextraction (HS-SPME) combined with gas chromatography-mass spectrometry (GC-MS), the floral volatile compounds of four lily (Lilium spp.) varieties at the early flowering stage and full blooming stage were analyzed. Quantitative real-time PCR (qRT-PCR) and neutral red staining experiments were employed to determine the relative expression levels of six key genes involved in floral scent synthesis and the scent-releasing sites in lily flowers during different stages. The results revealed that a total of 61 volatile compounds were identified in the early flowering stage and full blooming stage of the four lily varieties. The total volatile compound contents were higher in the full blooming stage compared to the early flowering stage. The major components with higher contents included linalool, (Z)-β-ocimene, 1,8-cinede, D-limonene myrcene, and methyl benzoate. Screening of differential volatile compounds identified 44 different compounds among the four varieties. The 61 volatile compounds were classified into nine major classes, the main volatile compounds of four varieties in early flowering stage and full blooming stage were terpenes and esters. The qRT-PCR results indicated that the relative expression levels of the PAL, PAL3, DXS, and TPS genes were higher in the full blooming stage compared to the early flowering stage in all four varieties. The relative expression levels of BSMT gene in full blooming stage of 'Siberia' and DXR gene in full blooming stage of 'Competition' and 'Conca d'Or' were lower than those in early flowering stage. The neutral red staining experiment revealed that the degree of staining was higher in the full blooming stage, with the upper half of the petals showing the deepest staining, indicating that this area was the main site for the release of floral scent compounds.