A tire load prediction system (S1) comprising: a sensor unit (SU) that is provided inside a tire and has a strain sensor (SN) that detects strain of the tire; a strain data acquisition unit that acquires strain data in a tire tangential direction that is output from the sensor unit; characterized that the system comprises: a linear transformation unit that performs a linear transformation on the acquired strain data; a first estimation unit that estimates a velocity and angular velocity in the tire tangential direction on the basis of a transformation result produced by the linear transformation unit; a second estimation unit that estimates a velocity in a tire radial direction from estimated values for the velocity and angular velocity in the tire tangential direction; a third estimation unit that estimates a velocity in a θ-angle direction corresponding to an angle of the strain sensor with respect to a ground contact surface of the tire, from estimated values for an acceleration and angular velocity in the tire tangential direction; a fourth estimation unit that estimates deflection of the tire on the basis of the velocity and angular velocity in the tire tangential direction, the velocity in the tire radial direction, and the velocity in the θ-angle direction; and a load prediction unit that predicts a load applied to the tire on the basis of the estimated deflection of the tire. a sensor unit (SU) that is provided inside a tire and has a strain sensor (SN) that detects strain of the tire; a strain data acquisition unit that acquires strain data in a tire tangential direction that is output from the sensor unit; characterized that the system comprises: a linear transformation unit that performs a linear transformation on the acquired strain data; a first estimation unit that estimates a velocity and angular velocity in the tire tangential direction on the basis of a transformation result produced by the linear transformation unit; a second estimation unit that estimates a velocity in a tire radial direction from estimated values for the velocity and angular velocity in the tire tangential direction; a third estimation unit that estimates a velocity in a θ-angle direction corresponding to an angle of the strain sensor with respect to a ground contact surface of the tire, from estimated values for an acceleration and angular velocity in the tire tangential direction; a fourth estimation unit that estimates deflection of the tire on the basis of the velocity and angular velocity in the tire tangential direction, the velocity in the tire radial direction, and the velocity in the θ-angle direction; and a load prediction unit that predicts a load applied to the tire on the basis of the estimated deflection of the tire. a linear transformation unit that performs a linear transformation on the acquired strain data; a first estimation unit that estimates a velocity and angular velocity in the tire tangential direction on the basis of a transformation result produced by the linear transformation unit; a second estimation unit that estimates a velocity in a tire radial direction from estimated values for the velocity and angular velocity in the tire tangential direction; a third estimation unit that estimates a velocity in a θ-angle direction corresponding to an angle of the strain sensor with respect to a ground contact surface of the tire, from estimated values for an acceleration and angular velocity in the tire tangential direction; a fourth estimation unit that estimates deflection of the tire on the basis of the velocity and angular velocity in the tire tangential direction, the velocity in the tire radial direction, and the velocity in the θ-angle direction; and a load prediction unit that predicts a load applied to the tire on the basis of the estimated deflection of the tire. <EOS>