An adjustable cable management arm devise. The device includes a pair of cable arms, pivotal pins, an adjustable arm, and an adjusting member. A first end of a first cable arm is connected to an end of a second cable arm, which is capable of folding each other, so as to form a combination of cable arms. The adjustable arm is inserted into an end of the combination of the cable arms and adapted to receive the pivotal pin. The adjustable arm is adapted to adjust a horizontal angle of a cable arm with respect to a wall bracket, so as to allowing the pivotal pin being smoothly rotated between the adjustable arm and the wall bracket.