This study investigates the influence of heat treatment on phase transformations, microstructures and mechanical properties of multilayered stainless steel VG-10/316L, in comparison to the properties of its constituent steels (martensitic VG-10 and austenitic 316L). The composite consists of a central martensitic VG-10 core layer, bordered by two multilayer sections comprising 33 alternating layers of austenitic stainless steel 316L and martensitic stainless steel 2Cr13, separated from the core by nickel interlayers. The research evaluates the mechanical response and microstructural behaviour of the VG-10/316L composite relative to its constituent steels, subjected to identical heat treatment processes. Heat treatment parameters were designed based on TTT diagrams and phase equilibrium analyses, with particular focus on martensite formation in the core layer and the stability of retained austenite. The study revealed that the multilayered composite exhibits significantly enhanced impact toughness, as measured by the Charpy impact test, while maintaining adequate hardness, evaluated through Vickers hardness testing, when compared to solid VG-10 steel. Microstructural analysis using light microscopy (LM) and scanning electron microscopy (SEM) highlighted distinct transformations across the layers, including variations in carbide distribution and differences in crack propagation between the VG-10 core and the 2Cr13/316L layers. Fractographic analysis further indicated fracture mechanisms, showing a predominantly ductile fracture in the 316L layers and a more brittle fracture in the 2Cr13 regions. The unique layered structure of the VG-10/316L multilayered stainless steel highlights its potential for applications requiring a balance of toughness, hardness, and structural integrity under thermal and mechanical stress conditions.