A grinding system comprising: a vertical roller mill including a rotating table, a grinding roller, and a housing, wherein raw materials are ground by the rotating table and the grinding roller in a grinding chamber formed in the housing while being dried by hot air, ground materials are discharged from a discharge port located lower than the rotating table, and gas containing fine powder generated by the grinding is discharged from a gas discharge port located higher than the rotating table; a ground material circulation system including a ground material circulation passage through which the ground materials discharged from the vertical roller mill move from the discharge port of the vertical roller mill to a supply port and a classifier (7; 46) provided at the ground material circulation passage and configured to classify the ground materials and separate refined powder from the ground materials; and a gas circulation system including a gas circulation passage through which the gas discharged from the vertical roller mill flows from the gas discharge port of the vertical roller mill to a hot air inlet, a powder collector provided at the gas circulation passage and configured to separate the fine powder from the gas, and said gas circulation system, comprised in the grinding system, being characterized by including a fan configured to suck the gas into the gas circulation passage, wherein the gas circulation system is independent from the ground material circulation system. a vertical roller mill including a rotating table, a grinding roller, and a housing, wherein raw materials are ground by the rotating table and the grinding roller in a grinding chamber formed in the housing while being dried by hot air, ground materials are discharged from a discharge port located lower than the rotating table, and gas containing fine powder generated by the grinding is discharged from a gas discharge port located higher than the rotating table; a ground material circulation system including a ground material circulation passage through which the ground materials discharged from the vertical roller mill move from the discharge port of the vertical roller mill to a supply port and a classifier (7; 46) provided at the ground material circulation passage and configured to classify the ground materials and separate refined powder from the ground materials; and a ground material circulation passage through which the ground materials discharged from the vertical roller mill move from the discharge port of the vertical roller mill to a supply port and a classifier (7; 46) provided at the ground material circulation passage and configured to classify the ground materials and separate refined powder from the ground materials; and a gas circulation system including a gas circulation passage through which the gas discharged from the vertical roller mill flows from the gas discharge port of the vertical roller mill to a hot air inlet, a powder collector provided at the gas circulation passage and configured to separate the fine powder from the gas, and said gas circulation system, comprised in the grinding system, being characterized by including a fan configured to suck the gas into the gas circulation passage, wherein a gas circulation passage through which the gas discharged from the vertical roller mill flows from the gas discharge port of the vertical roller mill to a hot air inlet, a powder collector provided at the gas circulation passage and configured to separate the fine powder from the gas, and said gas circulation system, comprised in the grinding system, being characterized by including a fan configured to suck the gas into the gas circulation passage, wherein the gas circulation system is independent from the ground material circulation system.