The kinematical measurement is regarded as the major indicator of the kinetic functions. In this study, we focused on developing a novel measurement method for kinematics of articulated finger in motion by using biomechanical model prediction and real-time video-based image analysis technique. In contrast to the marker-based system, the proposed 3D model provides more information, appearing on multiple projected 2D images, to estimate more reliable finger kinematics. The proposed method is compact, fast, and can be operated with X-ray fluoroscopy simultaneously. It means that the system provides the capability of synchronous validation between motion video and X-ray fluoroscopy. The proposed system was implemented on a personal computer and can be a new tool in diagnosis and rehabilitation for hand diseases.