Driving assistance method for a motor vehicle occupying a traffic lane, comprising the following steps: a) at least one datum relating to a position of the motor vehicle with respect to the traffic lane is acquired, b) a check is made as to whether the motor vehicle is departing from or is about to depart from said traffic lane unexpectedly, c) when said unexpected departure is detected, an intervention phase is triggered, during which a corrective torque (T C) is applied to said steering member for the motor vehicle to follow a target trajectory, the calculation of said corrective torque (T C) comprising the following operations: i) an effective steering angle (α E) of said steering member of the vehicle is acquired, ii) a target steering angle (α C) at which said steering member should be placed for the motor vehicle to follow said target trajectory is determined, as a function of the datum acquired in the step a), iii) a filtered target steering angle (α CF) is determined in such a way that: - at an initial instant of said intervention phase, the filtered target steering angle (α CF) is equal to the effective steering angle (α E) at this initial instant, then - after this initial instant, the filtered target steering angle (α CF) tends towards said target steering angle (α C), while exhibiting a rate of variation, the absolute value of which remains lower than a first determined threshold, and iv) said corrective torque (T C) to be applied is determined, as a function of this filtered target steering angle (α CF), characterized in that, during the operation iii), the filtered target steering angle (α CF) is determined in such a way that, in addition, as soon as the difference between the filtered target steering angle (α CF) and the target steering angle (α C) is cancelled or changes sign, the filtered target steering angle (α CF) tends towards said target steering angle (α C) while exhibiting a rate of variation, the absolute value of which remains lower than a second determined threshold which is higher than said first threshold. a) at least one datum relating to a position of the motor vehicle with respect to the traffic lane is acquired, b) a check is made as to whether the motor vehicle is departing from or is about to depart from said traffic lane unexpectedly, c) when said unexpected departure is detected, an intervention phase is triggered, during which a corrective torque (T C) is applied to said steering member for the motor vehicle to follow a target trajectory, i) an effective steering angle (α E) of said steering member of the vehicle is acquired, ii) a target steering angle (α C) at which said steering member should be placed for the motor vehicle to follow said target trajectory is determined, as a function of the datum acquired in the step a), iii) a filtered target steering angle (α CF) is determined in such a way that: - at an initial instant of said intervention phase, the filtered target steering angle (α CF) is equal to the effective steering angle (α E) at this initial instant, then - after this initial instant, the filtered target steering angle (α CF) tends towards said target steering angle (α C), while exhibiting a rate of variation, the absolute value of which remains lower than a first determined threshold, and - at an initial instant of said intervention phase, the filtered target steering angle (α CF) is equal to the effective steering angle (α E) at this initial instant, then - after this initial instant, the filtered target steering angle (α CF) tends towards said target steering angle (α C), while exhibiting a rate of variation, the absolute value of which remains lower than a first determined threshold, and iv) said corrective torque (T C) to be applied is determined, as a function of this filtered target steering angle (α CF),