The invention discloses a method for estimating an operating state of an SF6 high-voltage circuit breaker and an intelligent system, belonging to the technical field of electric transmission and transformation equipment. The intelligent system comprises a WEB server, a data server, an industrial personal computer, a local discharge monitoring unit, an opening / closing coil current monitoring unit, a release current monitoring unit, an opening / closing stroke monitoring unit, an opening / closing position monitoring unit, an SF6 gas temperature and pressure monitoring unit and a sensing element. The method comprises the steps of: 1, establishing an intelligent estimation system; 2, quantifying estimation indexes; 3, determining matter elements R to be estimated; 4, determining a model classic domain; 5, determining a model node domain; 6, calculating a subjective weight; 7, calculating an objective weight; 8, determining a subjective and objective combined weight; 9, determining a degree of association of the matter elements to be estimated; 10, estimating matter elements of a subproject layer; 11, estimating matter elements of a project layer; 12, estimating matter elements of a target layer; 13, determining an operating state grade; and 14, determining a characteristic index state grade trend. The invention has the advantages of simple model, visual estimation result and strong self-improvement characteristic.