The results of the observations of four southern barred spiral galaxies, NGC 613, NGC 1313, NGC 1566 and NGC 2442, with the SEST, in the ¹²CO(1-0) line, are presented. Mapping has been possible for three of the galaxies allowing the determination, for each of them, of the molecular surface density distribution and the velocity field, and, fro this, the rotation curve and the systematic velocity. Other parameters like the gas mass and kinematical total mass, were also possible to determine frm the position-velocity diagrams and the global profiles. Only in the case of NGC 1313 the detections were marginal so no mapping was possible.