Claude Alfred Jonnard (November 23, 1897 – August 27, 1959) was a professional baseball player.

He was a right-handed pitcher over parts of six seasons (1921–1924, 1926, 1929) with the New York Giants, St. Louis Browns and Chicago Cubs.

For his career, he compiled a 14–12 record in 137 appearances, most as a relief pitcher, with a 3.79 earned run average and 160 strikeouts.

Jonnard was a member of the Giants National League pennant-winning teams in 1923 and 1924, losing both World Series (to the New York Yankees and Washington Senators, respectively).

His twin brother, Bubber Jonnard, was a Major League catcher and coach.