Owing to their atomic thicknesses, atomically flat surfaces, long-range spin textures and captivating physical properties, two-dimensional (2D) magnetic materials, along with their van der Waals heterostructures (vdWHs), have attracted much interest for the development of next-generation spin-based materials and devices. As an emergent family of intrinsic ferromagnetic materials, Fe₃X(X=Ge and Ga)Te₂ has become a rising star in the fields of condensed matter physics and materials science owing to their high Curie temperature and large perpendicular magnetic anisotropy. Herein, we aim to comprehensively summarize the recent progress on 2D Fe₃X(X=Ge and Ga)Te₂ and their vdWHs and provide a panorama of their physical properties and underlying mechanisms. First, an overview of Fe₃X(X=Ge and Ga)Te₂ is presented in terms of crystalline and electronic structures, distinctive physical properties and preparation methods. Subsequently, the engineering of electronic and spintronic properties of Fe₃X(X=Ge and Ga)Te₂ by diverse means, including strain, gate voltage, substrate and patterning, is surveyed. Then, the latest advances in spintronic devices based on 2D Fe₃X(X=Ge and Ga)Te₂ vdWHs are discussed and elucidated in detail, including vdWH devices that exploit the exchange bias effect, magnetoresistance effect, spin–orbit torque effect, magnetic proximity effect and Dzyaloshinskii–Moriya interaction. Finally, the future outlook is given in terms of efficient large-scale fabrication, intriguing physics and important technological applications of 2D Fe₃X(X=Ge and Ga)Te₂ and their vdWHs. Overall, this study provides an overview to support further studies of emergent 2D Fe₃X(X=Ge and Ga)Te₂ materials and related vdWH devices for basic science and practical applications.