For the preventive design of marine fire, it is necessary to be grasped entirely the fire spread phenomena by an analysis taking thoroughly account of the governing factors and the characteristics of compartment fire. For that reason, the fire spreading phenomena in multi-compartments has to be simulated numerically by considering a distinctive feature of the turbulent diffusion of heat and atmospheric gas. In this paper, the turbulent heat diffusion field system consisted of the momentum and heat transportation are applied in the two dimensional calculation on multi-linked compartments with openings, while the gas balance equations with oxygen consumption and gas generation are solved by means of zone model. In order to investigate the threshold conditions of fire spread, some numerical simulations of fire accident in the multi-linked compartments were carried out on the variety of thickness of heat insulation.