In an active vibration isolation support system in which internal pressures of fluid chambers whose volumes are changed by a load applied from outside are controlled by an actuator that reciprocatingly vibrates a movable core on an axis by energizing a coil cylindrically wound around an outer periphery of a fixed core, an end surface of the coil on the fluid chambers side is inclined so that a radially outer side of the end surface is close to the fluid chambers with respect to the axis. Therefore, the output can be increased by increasing the number of windings of the coil without increasing the dimension of the active vibration isolation support system in the direction of the axis. Also, if the number of windings of the coil is made the same as that of the conventional system, the outer diameter of the coil can be made smaller than that of the conventional system accordingly to reduce the entire length of wire of the coil, thereby reducing the resistance and inductance to improve the electrical current response.