Ground dwelling and predating beetles, Carabidae (ground beetles) and Staphylinidae (rove beetles), are two important groups of predating insects in agricultural ecosystems. They have high species richness and population density and play crucial role in controlling pest insects and maintain health running of agricultural ecosystems. It is therefore very important to investigate their species composition, abundance and population dynamics (especially those changes relating to the pests), when pest control is mainly considered. According to our long-termed studies, we select here two methods, pitfall traps and haystick traps and introduce their general principle, usage, techniques and comparability in the field and procedures how to use them. We also discuss briefly how to build up sampling plots in the field and sampling bias that may disturbe the result analysis. We hope that this introduction may be helpful for field investigations.