Abstract: A ladder stabilizing device is adapted for attachment to a ladder and to a fixed structure for holding the ladder in a stable condition on a supporting surface adjacent to the structure. The ladder includes a base, a pair of laterally spaced side rails, and a plurality of vertically spaced and laterally extending rungs connected to the side rails. The ladder stabilizing device includes an elongate ladder locking member with a pair of spaced-apart locking grips for being releasibly locked in laterally spaced relation onto one of the rungs of the ladder. An elongate attachment member is rigidly coupled at its first end with the ladder locking member. The opposite second end of the attachment member is adapted for being secured to the fixed structure. A releasable fastener is located at the second end of the attachment member for releasibly attaching the stabilizing device to the fixed structure.