Traditional methods for detecting methane gas leaks mainly rely on single-point measurements and infra-red thermal imaging. However ,the former method has limitations due to low measurement point density and the ease with which gas can flow ,making it difficult to determine the exact location of the leak. The latter method relies on de- tecting and imaging gas plumes based on differences in temperature between the gas cloud and the surrounding environ- ment. When the temperature difference is small ,the imaging con-trast and resolution are often low. To address these limitations ,a new methane gas leak imaging detection technology has been proposed. This approach combines TDLAS remote sensing technology with laser ac-tive imaging methods to actively detect gas leakage areas. After detecting the gas leakage areas ,an algo - rithm that combines SSIM ( Structural Similarity Index Measure) and Gaussian Mixture Background Mod-eling is used to extract the gas leakage area ,achieving imaging detection of methane gas leakage plumes. Experimental testing was conducted on methane gas leaks under different conditions ,including various leakage flow rates ,video recording lengths ,and environmental conditions. The results showed that this technology can achieve active imaging detection of methane gas leaks ,with clear imaging ,high detection rates ,good real-time performance ,and accurate localization of gas leakage points.