Abstract. Real time and markerless motion capture is an active research area, due to applications in human-computer interactions, for example. A large part of the existing markerless motion capture methods require an initialization step, consisting in finding the initial position of the different limbs of the subject. In this paper, we propose a new method for interactive time initialization step, only based on morphological and topological information and which can be easily adapted to any kind of model (full human body or only hand, animals, for example). Key words: motion capture, initialization, markerless, skeleton, tree matching