In coal-fired power plants, the performance of the pulverizer is very influential on the overall performance of the power plant (heat rate). Pulverizer is used to crush coal, so it is designed to supply the right size of coal for combustion in the boiler. to get the optimum performance and capacity of the pulverizer, the pulverizer must be used according to the design of the pulverizer taking into account the index Hardgrove Grindability Index (HGI), raw coal size and moisture content. On the other hand, pulverizer performance also requires primary airflow and good coal fineness size, which is used as transportation air and primary combustion air in the boiler. This paper presents an experimental study into the effects of classifier vane opening integrated with primary air-fuel ratio (1,7:1; 1,8:1; and 1,9:1) to fineness production passed 200 mesh. In this experimental, the effects of opening classifier vane settings and primary airflow to coal fineness particle size and coal flow in coal pipe distribution were measured by using dirty pitot air test dan isokinetic coal sampling. Five different position opening of classifier vane settings and three variations different of primary air-fuel ratio were the test and the effect of fineness particle size resulting from was noted and counted. During the test, the operational data of the plant is still considered, to determine the effect of the test results on the flue gas temperature from flue gas temperature, reheater, and superheater attemperator spray flow because related to the combustion of fineness. the test results show that the opening set of the classifier with a 45% opening with 1,8:1 primary air-fuel ratio.