To provide an image blur detecting apparatus which accurately detects an image blur caused by a camera shake or the like by means of a relatively small-scaled circuit.

The image blur detecting apparatus includes: density projection value calculation units 1, 6 for calculating horizontal and vertical density projection values of an image regarding image signal sequentially input in the unit of a frame; and detection units 4, 5, 9, 10 for obtaining a degree of coincidence between an array of horizontal density projection values of a preceding frame and an array of horizontal density projection values of a current frame for each positional relationship while deviating the positional relationship of both sequentially in a vertical direction, detecting an image blurring amount of the current frame with respect to the preceding frame in the vertical direction on the basis of an obtained result, and also similarly detecting an image blurring amount in a horizontal direction.