Following the celebrated discovery of graphene, considerable attention has been directed towards the rich spectrum of properties offered by van der Waals crystals. However, studies have been largely limited to their two-dimensional (2D) properties, due to lack of 1D structures. Here, we report the growth of high-yield, single-crystalline 1D nanobelts composed of transition metal ditellurides at low temperatures (T~500°C) and in short reaction times (t £ 10 min) via the use of tellurium-rich eutectic metal alloys. The synthesized semimetallic 1D products are highly pure, stoichiometric, structurally uniform, and free of defects, resulting in high electrical performances. Furthermore, complete compositional tuning of the ternary ditelluride nanobelts is achieved with suppressed phase separation, applicable to the creation of unprecedented low-D materials/devices. This approach may be used as a general strategy for fabricating 1D layered nanostructures and is truly exciting opportunity that can lead to dozens of new 1D nanomaterials of electronic quality.