Abstract: A jet ski hull has a lower section formed with a pronounced and sharp leading keel portion defined by oppositely disposed curvilinear fluted side walls extending downwardly from the peripheral edge. The leading keel portion expands outwardly to define a central longitudinal flat bottom which divides each of the fluted side walls. A fluted longitudinal groove is formed along the outer edge of each of the fluted side walls, starting approximately at a point rearward of where the leading keel begins to flatten out.