We have fabricated van der Waals (vdW) Schottky junction between high work function conducting NbS₂ transition metal dichalcogenide (TMD) and semiconducting n-MoS₂ TMD for metal semiconductor field effect transistors (MESFETs). The Schottky barrier between NbS₂ and MoS₂ appeared as large as ~0.5 eV due to their work function difference, as measured by scanning Kelvin probe. Schottky effect MESFET operates with a low threshold gate voltage of -0.5 ~ -1 V exhibiting easy saturation. Since this FET contains low density traps at the vdW interface, little gate hysteresis and ideal subthreshold swing of 60~80 mV/dec are expected. In addition, source/drain (S/D) contact for n-channel MoS₂ could significantly affect device mobility. In the case of the graphene S/D contact, the device shows the highest mobility of more than 800 cm²/V s, although the device shows the lowest mobility of ~15 cm²/V s in the case of Au/MoS₂ contact without an annealing process. TMD-based MESFET with NbS₂/n-MoS₂ junction is considered novel and promising in future 2D device electronics.