Abstract: To solve the semantic uncertainty in computing with words (CW) and improve the power of word computing, the computing with words model based on Generalized Type-2 Fuzzy Petri Nets (GT2FPNCW) is developed on the basis of generalized type-2 fuzzy sets and Petri Network for refining semantic characteristics of words. The model is then extended to the rules of fuzzy logic reasoning to form a model of computing with word flow. Finally, the model is applied to an exemplary medical rescue system for testing its validity and rationality. The result shows that the model has good power of expression and generalization.