The geometric parameters of intermediate joints of medium voltage cables are the key to their structural design and electric field distribution simulation and analysis studies. In this paper, the structures of intermediate joints from nine different manufacturers are analyzed, and the statistics of each dimensional parameter are calculated to analyze the dispersion of structural dimensions of intermediate joints among manufacturers. The actual structure of the intermediate joints is modeled and simulated by selecting relevant structural parameters, and the effects of different design parameters on the electric field strength are investigated. While keeping other parameters consistent, it is found that the maximum field strength at the junction of the high-voltage shield with the main insulation and the cable insulation increases with the length L₂ of the high-voltage shield, and the relative growth rate of the maximum field strength reaches 16.66% when the difference in the length of the high-voltage shield between the intermediate joints of the two manufacturers is 50 mm. The maximum field strength at the intersection of the stress cone and the main insulation increases with the main insulation thickness d₁, and the relative growth rate of the maximum field strength is 7.36% when the difference of the main insulation thickness between the intermediate joints of the two manufacturers is 4.16 mm. The high voltage shield thickness d₂ has less effect on the field strength of the intermediate joints. The proposed intermediate joint structure dimensions provides important basic data for the design and simulation study of intermediate joints. It also provides an idea for optimization of intermediate joints.