Abstract: A mast base comprises a body, formed partly by a generally rectangular container (12), provided with four upper corner fittings (13), located at the upper end thereof, and with four lower corner fittings (14), located at the lower end thereof, and partly by a stationary supporting frame (15), placed upon the container (12) and attached to the four upper corner fittings (13). In order to support the body (12, 15) in a stable position on the ground, four supporting legs (16) are provided, which may be placed in positions, in which they project laterally each from one corner of the body (12, 15). Each supporting leg (16) is composed of one lower arm (18), at its inner end connected to a lower corner fitting (14), and one upper arm (17), at its inner end connected to the stationary supporting frame (15) or to an upper corner fitting (13). Moreover, at its outer end, each supporting leg (16) is provided with a supporting foot (32).