An exercise rowing machine of which a main shank has thereon a seat slidable relatively thereto, the shank has on its front end two lateral pedals, and has on its front and rear ends respectively two supporting racks, and has therebeneath at its central area a connecting seat pivotally connected with one end of an adapter of which the other end is connected with a buffer, so that the adapter can be waved to and fro by a force. The adapter connects a transverse rod of which two ends respectively pivotally connect two operating rods that each has an upper and a lower section bending inwards one relative to the other for an obtuse angle; the operating rods are provided symmetrically at the two lateral sides of the shank, thereby when the machine is rowed forwards and rearwards, touching of the body of a user can be avoided; and when the machine is folded and collapsed about the shank which is being as a middle line, storing and transporting spaces can be effectively reduced. The machine is applicable to use for indoor exercising.