Aiming at the problem that the development of a low loss threshing intelligent control system for corn kernel harvester is greatly affected by the experiment site and season, a set of hardware in loop simulation platform for low loss threshing intelligent control system was designed and developed. The simulation platform was composed of a simulation platform controller, operation panel, demonstration panel, armrest box, display, and upper computer. The composition of the intelligent control system for low loss threshing of the corn kernel harvester and the test requirements of the harvest controller was analyzed. The mathematical model of the adjustment process of the key operating parameters of the corn kernel harvester was established. The hardware in the loop simulation test system was built based on an STM32F407 single-chip microcomputer, and the testbed design was completed. The open-loop contrast test of operation parameter adjustment of the simulation platform and the corn grain harvester under no-load conditions was carried out. The mathematical expectation of the simulation error of the cylinder speed was 0.126r/min, and the standard deviation was 0.776r/min. The mathematical expectation of operating speed simulation error was -0.022km/h, and the standard deviation was 0.094km/h. The mathematical expectation of the concave clearance simulation error was 0.041mm, and the standard deviation was 0.147mm, which verified the effectiveness of the simulation platform for the adjustment process of the actuator of the corn harvester was verified. The signal simulation test and the automatic control strategy simulation test of the harvest controller were carried out. The results showed that the simulation platform can be used for the development of an intelligent control system for corn kernel harvester and the test of control strategy, which improved the system development efficiency and shortened the development cycle.