A general purpose full-field velocity measurement system based on the Particle-Imaging velocimetry (PIV) has been developed. This system is connected with the classical flow visualization technique (tracer injection method) and sophisticated image processing technique. The measurement system consists of a laser light source, a TV camera, a laser optical disk recorder and an image processor interfaced with a 16 bit micro-computer. The tracer particles injected into the liquid flow are illuminated using the pulsed laser light sheet and are tracked by the TV camera. The images recorded on the laser disk are later replayed and sent to the image processor, and instantaneous velocity vectors of whole flow field is automatically calculated. To explore the ability and usefulness of this system the complex flow field in a casting model have been investigated.