The fracture behavior of three-layered stainless plates was investigated, related to each layer thickness. The layered plates were prepared by explosive bonding. The central layer consisted of a SUS 304 plate and both surface layers consisted of SUS 316 LN plates. The fracture toughness test for the plates was conducted at 77 K. Every crack was extended in the edgewise direction of each plate. The experimental procedure conformed to ASTM E 813-81 standards. The crack extension of the plates were calculated as the average of the ones in the flatwise direction. It is understood that the elastic-plastic fracture toughness, JIC, and the tearing modulus, Tmat, increase with an increase in the total thickness of SUS 316 LN of both surface sides, and these values correspond with the law of mixtures. The JIC and Tmat, which were evaluated by the crack extension of the central SUS 304 layer only, are higher than those of the SUS 304 base material.