The invention discloses a submarine cable carrying capacity onshore simulation experiment device and method. The submarine cable carrying capacity onshore simulation experiment device includes a thermocouple, a temperature acquisition module, a fiber temperature strain analyzer, a core-piercing transformer, and a current transformer, used for simulating the structure of an actual submarine cable bundled optical cable. The actual submarine cable operation condition can be simulated by the onshore simulation experiment, so that the actual situation of the submarine cable bundled optical cable structure is simulated, and the costs are saved. The method realizes the measurement of the temperature of each position of the cable and the optical cable under different currents of the cable bundledoptical cable, and deduces the relationship between the temperature and the current; the analog simulation is carried out by the COMSOL simulation software, and the simulation results is compared withthe experimental results, so as to provide ideas and correction methods together for the model construction of monitoring the actual carrying capacity of the submarine cable; moreover, it is verifiedthat the temperature of the optical fiber in the optical cable can be used for monitoring the temperature of the cable, and the method for estimating the carrying capacity is feasible, therefore, themonitoring idea and method for the actual submarine cable bonded optical cable structure are provided.