Gestures have been employed for human computer interaction to build more natural interface in new computational environments. In this paper, we describe our approach to develop a gesture interface using spatial context information. The proposed gesture interface recognizes a system action (e.g. commands) by integrating gesture information with spatial context information within a probabilistic framework. Two ontologies of spatial contexts are introduced based on the spatial information of gestures: gesture volume and gesture target. Prototype applications are developed using a smart environment scenario that a user can interact with digital information embedded to physical objects using gestures.