The invention relates to a floating platform (1) for offshore drilling or production of hydrocarbons, comprising a topsides (2) and a substructure (3) having a lower pontoon (4) and columns (5) connecting the pontoon (4) to the topsides (2). Heave motion (s.sub.1, s.sub.2) of the platform (1) causes a change in the metacentric height (GM) of the platform. To counteract this change in metacentric height, the columns (5) are so adapted that the moment of area inertia of the waterline area of the columns (5) decreases on downward heave motion (s.sub.1) and increases on upward heave motion (s.sub.2).