Interfacial atomic configuration plays a vital role in the structural stability and functionality of nanocomposites composed of metal nanoparticles (NPs) and two−dimensional semiconductors. In situ transmission electron microscope (TEM) provides a real−time technique to observe the interface structure at atomic resolution. Herein, we loaded bimetallic NiPt truncated octahedral NPs (TONPs) on MoS2nanosheets and constructed a NiPt TONPs/MoS2heterostructure. The interfacial structure evolution of NiPt TONPs on MoS2was in situ investigated using aberration−corrected TEM. It was observed that some NiPt TONPs exhibited lattice matching with MoS2and displayed remarkable stability under electron beam irradiation. Intriguingly, the rotation of an individual NiPt TONP can be triggered by the electron beam to match the MoS2lattice underneath. Furthermore, the coalescence kinetics of NiPt TONPs can be quantitatively described by the relationship between neck radius (r) and time (t), expressed asrn= Kt. Our work offers a detailed analysis of the lattice alignment relationship of NiPt TONPs on MoS2, which may enlighten the design and preparation of stable bimetallic metal NPs/MoS2heterostructures.