An empirical non-linear model for SOI MOSFET useful for large-signal simulations of high frequency circuit design is presented. An original close form expression is proposed for the drain current and charge conservation is taken into account, as capacitances are derived from a single charge model. The model's parameters are first extracted, prior the model implementation in a circuit simulator. Then some comparisons with experimental data are proposed to validate the model. Note that the model is well suited for the Fully Depleted either the Partially Depleted devices.