This paper proposes an extended COLLADA-based File Format to support various attributes of realistic objects for Virtual Reality (VR) applications. VR applications provide the user with virtual objects represented as 3D CG. To provide realistic virtual objects in a VR application, the developer of the VR application has to define many attributes of the corresponding real objects besides their 3D geometry and material data in his/her program or in instance definition files of the virtual objects. In this paper, the authors propose the use of a COLLADA file format for such instance definition of virtual objects because it is a XML based 3D model data format and can be easily extended to additionally include various attributes of the virtual objects. This paper introduces the proposed COLLADA-based file format that mainly supports three types of attributes. Those are haptic parameters of soft objects represented by the spring model used for a haptic device like Phantom, text data used as annotations for explaining corresponding objects helpful in simulation/training systems and smell information of objects used for smell generator devices to enhance immersive feeling in VR applications. This paper also clarifies the usefulness of the proposed COLLADA-based file format by showing its examples of actual VR applications.