Thermal transport is one of the key factors in defining the performance of thermoelectric (TE) materials, given that most of these cannot combine high power factor with low thermal conductivity^[1]. Nevertheless, thermal transport in van der Waals (vdW) materials and their heterostructures could be tweaked, leaving an open platform for new TE applications^[2]. In particular, indium selenide (InSe) shows high TE potential due to advantageous electrical and thermal properties, increasing the TE efficiency^[3]. Here we quantify the thermal transport in γ-InSe nanolayers via x-section scanning thermal microscopy (xSThM), providing a key insight to its in-plane and cross-plane thermal conductivities as well as interfacial thermal resistance to the substrate^[4,5].