A heavy duty pneumatic tire includes a tread portion provided with circumferentially extending zigzag shaped main grooves, a plurality of land portions separated by the main grooves, and a plurality of lateral grooves to form a plurality of block elements on each land portion. Each land portion comprises a number of pitches in a range of from 40 to 50, wherein each pitch consists of one block element and one lateral groove adjacent to the concerned block element. Each block element has a length in a range of from 85% to 95% of a length of the pitch. The main grooves include a crown main groove, a shoulder main groove, and a middle main groove. The middle main groove has a zigzag amplitude larger than those of the crown main groove and the shoulder main groove.