Abstract：The mercury vapor and its compounds would be relatively concentrated to form mercury gas halo in geological structure, metallic ore deposits, pollution sources and such places as ancient tombs and ruins. These characteristics of mercury can be utilized to conduct mercury survey, geological structure investigation, mineral exploration and pollution source delineation so as to apply mercury more extensively in industrial and agricultural production. The authors made a simple description of the method and instrument principle and discussed in detail the analytical means and application results of trace and minor amounts of mercury in various kinds of samples. Aimed at solving such problems in mercury analysis as the complex operation before processing and poor reproducibility, the authors put forward the utilization of the direct mercury measurement method to determine the mercury in solid powder samples. With this method, samples don't need being processed, and mercury waste gas will be discharged after harmless treatment with absorbing agent. The method is characterized by fast analysis and high accuracy; in addition, it needs no chemical reagent and has no harm to human body.