A lacrosse helmet comprises rigid single-piece shell formed of a suitable material such as polycarbonate or ABS plastic and adapted to receive and protect the head of a wearer. The shell has acclivities integrally formed therein to define features in the shell. Two alternative padding assemblies are disclosed. In a first alternative, the padding assemblies include a front liner installed in the brow area of the shell, a lateral padding assembly extending around the back inner surface of the shell and backed by an inflatable occipital pad, a crown shock absorber, and jaw pads. In a second alternative, the padding assemblies include an inner shell or bonnet comprising a left section, right section, and rear section, which are assembled together with a crown comfort layer and a rear comfort layer, and inserted into the shell. This alternative also includes jaw pads as in the first alternative.