An exercise ball device for exercising by a user while in a prone position. The exercise ball device includes a semi-circular shaped housing having an outer curved surface and an interior curved compartment having an inner curved surface. The housing has a retaining member positioned on the perimeter edge of the housing. The exercise ball device also includes a rolling ball positioned within the interior curved compartment, and the rolling ball is removably restrained within the interior curved compartment by the retaining member. Further, the outer curved surface of the housing has a restraint member attached thereto for receiving the hand of a user. Additionally, the rolling ball is approximately the same size as the interior curved compartment so that the rolling ball rotates or rolls within and relative to the housing.