We present results of numerical simulation of dissociation behavior of methane hydrates in laboratory experiments conducted at the Institute for Geo-Resources and Environment in Tsukuba, Japan. The hydrate was formed in packed sand columns and the dissociation behavior was studied under different stimulation conditions including hot-water injection and/or pressure reduction. A number of variables including amount of gas produced, temperature along the column and pressure difference across the column were monitored. A numerical model for hydrate behavior was developed, based on the FEHM (Finite Element Heat and Mass) Computer Code, the Los Alamos National Laboratory (LANL)'s in-house porous flow simulator. Capability to simulate the general behavior of hydrates in porous media was added to the simulator, including the kinetic, thermodynamic and heat transfer processes. Multiple conceptual models were used to simulate the experimental data. The simulation results indicate that incorporation of both dissociation and hydrate formation is necessary to better match the experimental data.