This paper reports on the fabrication of a ferroelectric field effect transistor (FeFET) using a monolayer MoS2 film and a perovskite GdNi0.2Fe0.8O3 (GFNO) ferroelectric film. We demonstrate the tuning of electrical characteristics using pulse voltage to evoke a 2H-1T′ phase transition in the MoS2. Coupling at the MoS2-GFNO interface is the mechanism responsible for the electronic tuning. Locally reversing the ferroelectric polarization of the perovskite GFNO through the application of pulse voltage makes it possible to manipulate the carrier concentration and associated phase of the MoS2 via heterostructure interactions. Our experiment results are supported by free energy calculations pertaining to heterostructures under the effects of an electric field. Analysis of the nonvolatile properties of the FeFET using the scanning probe method and scanning photoelectron spectroscopy revealed that the transition indeed occurred across much of the device landscape. The design established in this study paves the way to the development of laterally two-dimensional FeFET, which could provide nonvolatile characteristics with a less destructive read-write process.