The influence of stand density on the resin duct morphological structure and terpene components of Pinus massoniana were studied. The resin duct morphological characteristics and the relative content of the terpene components were investigated by microscopy and gas chromatography-mass spectroscopy, respectively. The experimental results revealed that there was a specific correlation between the stand density and resin duct area, resin duct diameter, and the relative contents of main terpene components in the turpentine extracts. Additionally, the relative contents of β-pinene and (+)-camphene were positively correlated with stand density, with correlation coefficients of 0.8208 and 0.5539, respectively. In contrast, the relative contents of (+)-longifolene and (+)-longicyclene were negatively correlated with stand density, with correlation coefficients of -0.5750 and -0.7726, respectively, and α-pinene, β-caryophyllene, and (+)-α-longipinene had no correlation with stand density. The relative content of (+)-α-pinene was negatively correlated with the relative contents of both (+)-longifolene and (+)-longicyclene, with correlation coefficients of -0.8770 and -0.8914, respectively. There were positive correlations between the relative contents of (+)-longifolene and (+)-longicyclene with correlation coefficient of 0.9718, (+)-longifolene and (+)-α-longipinene with correlation coefficient of 0.8399, β-caryophyllene and (+)-α-longipinene with correlation coefficient of 0.9360, and (+)-longicyclene and (+)-α-longipinene with correlation coefficient of 0.8626.