A new approach to definition of the term "active volcano" has been worked out on the basis of detailed reconstruction of the eruptive activity of Kamchatka volcanoes. We suggest to consider active those poligenous volcanoes whose at least a single eruption has been ascertained and dated over the last 3000-3500. Two sub-groups of active volcanoes have been distinguished: sub-group of active volcanoes with data available on the historically documented eruptions or fumarolic activity and the one of potentially active volcanoes without such data but whose eruptions have been revealed over the last 3500 years. Using similar criteria the potentially active fields of the areal basalt volcanism, regional zones of cinder cones and concentrated manifestation of the multivent extrusive volcanism are also distinguished. We propose to use data obtained for the new catalogue of active Kamchatka volcanoes and for the long-term prediction of volcanic activity and associated hazard.