Abstract: Based on the on-site production test of high grade non-oriented silicon steel, continuous casting slabs of the same furnace were hot-rolled to coils of different thicknesses (2.1, 2.3, 2.6 mm), and then subjected to regular homogenization process control to obtain a normalized plate structure with relatively uniform grains. After cold rolling at a reduction rate of 85.7% to 88.5%, cold-rolled plates with the same thickness of 0.3 mm were obtained. Finally, annealed plates were obtained using the same annealing process. By combining relevant testing and analysis of organization, texture, and magnetic properties, the influence of hot-rolled plate thickening on the magnetic properties of high grade non-oriented silicon steel product was studied.The results show that as the thickness of hot-rolled plate of high grade non-oriented silicon steel increases (in the range of 2.1–2.6 mm, i.e., the cold rolling reduction rate decreases), the proportion of 111 grain in the annealed plate structure increases, the strength of the γ fiber texture gradually increases, and the texture deteriorates. As the thickness of the hot-rolled plate increases, the iron loss P_1.0/400 in the magnetic properties linearly increases, while the magnetic induction intensity B₅₀ linearly decreases. When the thickness of hot-rolled plate increases from 2.1 mm to 2.3 mm, the average deterioration of P_1.0/400 is 0.20 W/kg, P_1.5/50 is 0.04 W/kg, and the average deterioration of B₅₀ is 0.005 T. When the thickness of hot-rolled plate increases from 2.3 mm to 2.6 mm, the average deterioration of P_1.0/400 is 0.24 W/kg, P_1.5/50 is 0.04 W/kg, and the average deterioration of B₅₀ is 0.009 T.