The invention provides a method of precisely measuring the volume of a hydrocarbon inclusion. The method comprises steps: 1, a laser scanning confocal microscopy is adopted for scanning, and a three-dimensional image of the hydrocarbon inclusion is acquired; 2, under transmission light and fluorescence, a three-direction coordinate is used for demarcating the liquid-phase boundary of the three-dimensional image; 3, according to the demarcated liquid-phase boundary, the liquid-phase volume of the hydrocarbon inclusion is calculated; 4, a laser scanning confocal microscopy fluorescence spectrum is used for precisely acquiring the gas-phase diameter d and the gas-phase radius R in the hydrocarbon inclusion; and 5, according to a formula V=(4/3)piR<3>, the gas-phase volume V of the inclusion is calculated. The method of precisely measuring the volume of the hydrocarbon inclusion of the invention adopts a mode of manually synthesizing a hydrocarbon inclusion standard sample for verification, and the measurement precision is obviously improved compared with that in a previous technology.