— This paper presents a new mathematical model for the human behavior called Stochastic Switched Linear Dynamical (SS-LD) model. The SS-LD model can be regarded as a natural extension of the conventional Hidden Markov Model (HMM), where different Linear Dynamical model is allocated to each discrete state of the HMM to represent continuous dynamics. Then, the parameter identification technique for SS-LD model is developed based on the EM algorithm. Finally, we apply the proposed behavior model to a typical man-machine cooperative system, and the usefulness of the proposed model is verified through some experiments.