The work aims to study the coil steel transportation mode of 20 ft (1 ft=304.8 mm) 35 t open top containers under the background of China's great efforts to develop container multimodal transportation, design two types of coil steel frames according to different specifications of coil steel, and analyze and verify their strength performance. The SolidWorks software was used to establish a three-dimensional model of the frames. The Ansys Workbench software was used to analyze the displacement and stress changes of the frames under static load and impact conditions, and then the static load and impact tests were carried out. According to "Reinforcement Rules for Railway Cargo Loading" and "Strength Design and Test Accreditation Specification for Rolling Stock-Car body-Part 2:Car Body of Freight Wagons", the simulation results were compared with the test results. The displacement and stress deformation of the simulation results did not exceed the maximum allowable value of structural materials under static load and impact conditions. The test results showed that the front and rear frames were in good conditions without obvious damage and deformation. The maximum absolute deviation between the simulation analysis results and the test results of these two types of frames was only 20.19 MPa and 22.23 MPa, indicating that the simulation analysis results had great accuracy. The model of 20 ft 35 t open top coil steel transport frame designed in this work is reasonable. Its strength is in line with the specification requirements and can meet the needs of safe and efficient transportation of coil steel.