Abstract: Gap-phase replacement of trees was studied in a secondary conifer broad-leaved mixed forest distributed widely in Jinyun Mountain, Chongqing and successional trends in gaps and forest type were predicted. The results show that while Pinus massoniana has an intense reciprocal replacement pattern, Gordonia acuminata, Symplocos setchuanensis and other evergreen broad-leaved tree species display both self replacement and reciprocal replacement patterns. The current tree replacement process in gaps does not appear to act towards the maintenance of the current community composition. The analysis of Markov transition matrix shows that the Pinus massoniana population will lose its dominant position in the future composition of the forest canopy. The whole community is in a succession process from a conifer broad-leaved mixed forest to an evergreen broad-leaved forest.