Recently, Island kitchen is installed in many houses in Japan. In the island kitchen, the cooking range is placed on the island unit, and the center hood is located above the cooking flow in the room. In such a kitchen environment, there is a possibility that cross winds or other disturbing flow may reach the cooking zone. For this reason, pollutant fumes from the cooking range may be diffused to residential zone. CFD analysis is an effective measure for comprehending such a diffusion of the thermal plume. In comprehending the diffusion of the thermal plume above the cooking range by CFD analysis, a variety of plume models are proposed as boundary conditions. In this study, “Pot-side wall jet model” is proposed. The velocity and temperature around the pot side are measured, and the profiles are regressed to formula of two-dimensional jet flow. This means that the thermal plume with high temperature from the gas cooking range is modeled. This paper aims to demonstrate the usefulness of Pot-side wall jet model in analyzing the thermal plume in the large laboratory where a gas cooking range with a pot is only installed. In this paper, the results of CFD analysis are compared with the experimental results.