The invention provides a method and a device for measuring decrepitation, expansion and shrinkage performance of a lump coal. The device comprises a heating system, a camera, a computer, a light source adjustment system and an atmosphere system, wherein the heating system comprises a furnace tube, a quartz window, a sample substrate, a sample and a temperature measuring thermocouple, wherein the top of the thermocouple contacts the sample substrate closely; the lens of the camera is a long-focus charge coupled device (CCD) lens; and the heating system is arranged right ahead of the CCD lens. The method comprises the following steps: heating a lump coal sample in the device; selecting a proper temperature point to collect an image when the image is clear; calculating the expansion rate and shrinkage rate of the volume. The pyrolyzation and degassing processes of the lump coal can be visually observed at different temperatures through providing a visual device and the measurement method; the expansion and shrinkage behavior and the decrepitation of the lump coal can be indirectly measured through image collecting, thus providing guidance basis for the use of the lump coal in a melting gasification furnace.