To investigate the chemical constituents of the pine cones of Pinus massoniana Lamb. and their anti-inflammatory activities, this study employed silica gel chromatography, gel column chromatography, reverse-phase ODS column chromatography, and other methods to separate the 85% ethanol extract of P. massoniana cones. The compounds were structurally determined by NMR and MS analyses, and their identity was verified against known literature data. The mouse mononuclear macrophage leukemia cells (RAW 264.7) were cultured in vitro. A cellular inflammation model was established by inducing RAW 264.7 cells with lipopolysaccharide (LPS), and the anti-inflammatory activity of compounds was determined using a nitric oxide kit. Nineteen compounds were finally isolated and identified from the plant as pyrocatechol (1), p-hydroxybenzaldehyde (2), protocatechuic acid (3), vanillic acid (4), ethyl 3,4-dihydroxybenzoate (5), 3,4-dihydroxyacetophenone (6), rhodoendrol (7), 5,4′-dihydroxy-3,7,8-trimethoxy-6-methylflavone (8), (2R)-5,4′-dihydroxy-6-C-methyl-7-methoxy-flavanone (9), 5,7-dihydroxychromanone (10), 2′,4′-dihydroxy-4,6′-dimethoxydihydrochalcone (11), pinocembrin (12), kaempferol (13), quercetin (14), 6-methylaromadendrin (15), sagebrushin (16), C-6,O-7-dimethylaromadendrin (17), rhododendrin (18), and 8-desmethylrhodododendrin (19). Among them, compounds 1, 5, 6 ,8-11, 14, 17-19 were isolated from P. massoniana for the first time, and compounds 5, 6, 9-11, 14, 18 were isolated from the genus Pinus for the first time.The results of anti-inflammatory activity showed that compounds 5, 6, 8-19 inhibited LPS-induced NO release in RAW 264.7 cells, with compounds 13 and 18 exhibiting stronger inhibitory activity (IC₅₀ = 2.32 ± 0.99 and 6.13 ± 0.86 μmol/L, respectively).