The invention discloses a thyristor press-fitting structure in a modular multilevel converter power module. The structure comprises two pressure dispersion plates. The two pressure dispersion plates are connected through a bolt pair to form a support frame of the pressure-fitting structure. Anode side and cathode side of a thyristor are respectively provided with a positive busbar and a negative busbar. Two sides of the thyristor provided with the positive busbar and the negative busbar are respectively equipped with an insulating block, and then the insulating blocks are clamped and fixed between the two pressure dispersion plates. By a pressing mode of the bolt pair, the pressure dispersion plates fix the insulating blocks, the positive busbar, the negative busbar and the thyristor. The pressure-fitting structure is simple and is convenient to install and dismantle. The thyristor is uniformly forced. The insulating blocks are respectively installed at the anode side and the cathode side of the thyristor, thus easily keeping consistent with the axis of the thyristor. Therefore, crimping force uniformity of the thyristor is guaranteed.