China's steel industry has a huge demand for imported iron ore and does not have the pricing power for imported iron ore, so there is a high risk in the supply of iron ore. Since there are many factors affecting the price of imported iron ore and they are interrelated, there is still a lack of authoritative research results on the causes of fluctuations in the spot price of imported iron ore. Based on the existing research on the price of imported iron ore, factors such as iron ore supply and demand, transportation costs, pricing models, finance, and economic development were selected as factors affecting the price of iron ore, and determines the relevant representative indicators of each factor. By constructing a Lasso regression model, the main influencing factors of the spot price of imported iron ore and the complex interactive relationship between these factors are clarified, and the influence of each influencing factor is identified by the variance decomposition method. The results show that the Platts iron ore price index, shipping index, US dollar index, and domestic iron ore production are the main factors affecting the spot price of imported iron ore, among which the Platts iron ore price index is the most critical factor. Based on the model results, it puts forward corresponding policy recommendations from the perspectives of strengthening iron ore market supervision and optimizing iron ore transportation costs.