Abstract: With the rapid development of fourth-generation nuclear reactors and new nuclear energy utilization systems, as well as advancements in research areas such as superheavy nucleus fusion mechanisms and fast neutron capture reactions in astrophysical nuclear physics, neutron-induced heavy nucleus fission studies and fission data measurements have become a significant topic of international nuclear physics research. In this study, we present the physical design of a neutron-induced fission spectrometer using the velocity-kinetic energy (v-E) method. The MCP secondary electron time detector was designed with the spread of secondary electron flight time controlled at 50 ps, and the TOF flight distance was designated for 70 cm. For the energy detection, we selected the Frisch-Grid Ionization Chamber (FGIC) with isobutane as the working gas. The optimal reduced electric field was 6 V/(cm·133.32 Pa), and the optimal pressure was 5000 Pa. The energy response of the fission fragments in chamber was calculated by coupling programs such as COMSOL, Geant4, and Garfield++, and the energy resolution is from 0.36% to 0.55%. The fission spectrometer designed in this work has a mass resolution of less than 1 amu, provided that the energy resolution of light fragments is less than 0.8% and that of heavy fragments is less than 0.6%. Additionally, based on the physical structure of the fission spectrometer, the mass distribution and charge distribution data of ²³⁸U fission yield induced by 14 MeV neutron are simulated in this work, which is basically in agreement with the ENDF-VII, preparing the conditions for experimental measurements of neutron-induced fission physics of typical actinide heavy nuclei.