Abstract: It has been known that eclogites have a diversity in the mode of occurrence and petrology. In this paper, eclogites and eclogitic rocks are divided into two types, i.e., prograde and retrograde eclogites, based on the P-T paths of the equilibration leading to the eclogite facies mineralogy. The prograde eclogite was recrystallized from hydrous phases, and the retrograde eclogite is defined by its formation from higher temperature anhydrous phases. The following features help to identify the prograde eclogites: I. Regional distribution of eclogite facies a) Mapping of prograde mineral zones to reveal the dehydration reaction to form eclogites. b) Mapping of the progressive thermal gradient in the zone of the eclogite facies. II. Presence of such hydrous minerals as epidote, amphibole, chlorite and micas as the inclusions in the eclogitic garnet and omphacite. III. Progressive zonal structure of the eclogitic garnet and omphacite. Based on these criteria, the eclogites from New Caledonia, Tauern Window and Sesia Lanzo zone in the Alps, Caledonian belt in Norway, and Sebadani in the Sambagawa metamorphic belt are classified into the prograde eclogite. At least two metamorphic facies, the glaucophane schist and epidote amphibolite facies, are confirmed for the pre-eclogite stage of the prograde eclogite. The transition from the glaucophane schist facies to the eclogite facies has been described in the New Caledonia and Sesia Lanzo zone, while that from the epidote amphibolite facies to the eclogite facies is observed in the Tauern Window, Norway and the Sambagawa metamorphic belt. The nature of the metamorphic facies on the lower grade side of the eclogite facies depends on the pressure, and the higher pressure prefers the glaucophane schist to the epidote amphibolite facies.