This paper deals with the delamination in composite laminates based on the authors' sublaminate model. General expressions for total energy-release rate and for its individual components are derived for multiple delaminations on different interfaces. In each sublaminate, generalized strain and stress are given, and the total strain energy of the laminate is derived. The delamination growth is treated as a variational problem with moving boundaries. The total energy-release rate is derived first in terms of stress resultant jumps, and then the relative displacements between delamination surfaces are examined. As examples, the authors consider the effect of number of sublaminates on the energy-release rates, study an one-dimensional multiply delaminated cantilever beam, and examine a non-homogeneous edge-delaminated composite laminate. The results are in good agreement with those given hitherto.