A heavy duty pneumatic tire includes a tread portion 2 provided with circumferentially extending zigzag shaped main grooves 3 , a plurality of land portions 4 separated by the main grooves, and a plurality of lateral grooves 5 to form a plurality of block elements 6 on each land portion. Each land portion comprises a number of pitches P 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 3C , a shoulder main groove 3S , and a middle main groove 3M . The middle main groove has a zigzag amplitude MW1 larger than those of the crown main groove CW1 and the shoulder main groove SW1 .
