Abstract: Low strain reflected wave method has been a widely used technology of pile foundation detection recently. In connection with common engineering quality problems in the foundation construction progress, such as broken pile, necking, widening from folding and other problems, this paper illustrates the basic principles of low strain reflected waves law briefly. Meanwhile, combining with the filed data collection and the indoor trail data analysis, it investigates preliminarily the pile detection with the low strain reflected wave method,and it has got a corresponding verification from engineering practice.