In this paper, after analyzing other models with their advantages and disadvantages, we proposed a simple parametric model for calculating wind speed & direction and wave height & direction at any location around the typhoon at sea. The proposed wind-field model of typhoon is asymmetric, and consists of a circular symmetric wind-field caused by the pressure gradient of stationary typhoon and a moving wind-field caused by the movement of typhoon. By verifying this model through observed data, we found that it is accurate enough to develop the simulation software for training students and seafarers so as to take appropriate actions while being faced with the typhoon at sea.