Human-computer interaction technology based on virtual hand is a research focus of virtual reality. The key technologies were studied, the modeling method of polygon mesh was used and a realistic geometric model of virtual hand was established. The data acquisition module of data glove based on Virtools was developed and a method of data conversion based on initial value was proposed, the phenomenon of jump was solved when the virtual hand begin to move. For the fingers outreach motion, the method of constraint value was used, and the matching consistency of virtual hand with the real hand was increased. At last, for the interaction operation of virtual hand with virtual objects, a crawl algorithm based on effective threshold angle was put forward. Verified by Virtools platform, high fidelity of the virtual hand model is got, the shape of the hand changes naturally. Meanwhile, the interaction operation of virtual hand to virtual objects is implemented and it has a strong practicability.