Steering control apparatus for a vehicle

Whether a driver is driving intentionally is determined rapidly and accurately when steering control is performed such that a vehicle travels along recognized travel partitioning lines. A torque value deviation absolute value (TRQDEF_ABS (=TRQ - TRQOLD)) is calculated (step S02) using the absolute value of a difference between the torque value from the previous processing (TRQOLD) and the torque value from the current processing (TRQ), and is stored in a ring buffer (step S03). A torque value deviation sum value (TRQDEF_SUM) is calculated (step S04) by adding all the torque value deviation absolute values (TRQDEF_ABS) stored in the ring buffer, and when a state in which the torque value deviation sum value (TRQDEF_SUM) is equal to or less than a predetermined driving intention determination threshold (TH1) continues for a predetermined first threshold time (T1) (for example, several seconds; e.g. 5 seconds) or longer (YES in step S08), it is determined that there is a decrease in the driving intention (step S09).