Photoacoutic spectroscopy (PAS) plays an important role in trace gas sensing. Researchers are focusing on improving the performance of PAS-based gas sensors to satisfy different applications. As a promising way to promote the detection sensitivity, power-enhanced PAS has attracted increasing attention in this field with many breakthroughs. This article aims to discuss the status of this important research field, starts from classifying the most used and different technologies to summarizing the fundamental, technical characteristics and current achievements, towards a reasonable development tendency analysis.