Throwing, commonly referred to as chucking, is an illegal bowling action in the sport of cricket. This occurs when a bowler straightens the bowling arm when delivering the ball. Throws are not allowed when a bowler bowls to a batsman. If the umpire deems that the ball has been thrown, they will call a no-ball, which means the batsman cannot be given out from that delivery.

After biomechanical testing showed that all bowlers flex their extended arms to some degree, rules were changed. Current regulations of the International Cricket Council (ICC) set a limit of 15 degrees of permissible straightening of the elbow joint for all bowlers in international cricket. This law applies between the point at which the bowling arm passes above shoulder height and the point at which the ball is released. The limit is to allow only the natural flexing of the elbow joint which happens during the course of legal delivery.

The charge of 'throwing' against a bowler is one of the most serious and controversial that can be made in cricket, as a bowler with an illegal action must take steps to correct their action or face being banned from the game.

Law 21, Clause 2 defines a fair delivery with respect to the arm:

A ball is fairly delivered in respect of the arm if, once the bowler's arm has reached the level of the shoulder in the delivery swing, the elbow joint is not straightened partially or completely from that instant until the ball has left the hand. This definition shall not debar a bowler from flexing or rotating the wrist in the delivery swing

Before the advent of developed biomechanical and audiovisual technology, Law 24 Clause 3 was implemented by the field umpires, who judged a delivery as illegal or "thrown" on visual judgement alone. The law against throwing has not changed in its essence since overarm bowling was legalised in 1864.

Tom Wills, Australia's most revered cricketer of the mid-19th century, was also its most controversial. He was often accused of throwing and later even admitted to it. Many of his contemporaries recalled his trickery: "[Wills] used to say to the umpire, 'Just look at my feet, will you; I have a bad habit now and then of going over the crease.' The umpire would look at Tom's feet, and Tom would let go a throw for all he was worth." In 1872 Wills became the first cricketer to be called for throwing in a major Australian match, effectively ending his first-class career.

In the early 1880s there were a number of bowlers who were widely considered to have unfair actions, with the Lancashire pair of Jack Crossland and George Nash coming in for particular criticism. After playing for Kent against Lancashire in 1885, when he faced the bowling of Crossland and Nash, Lord Harris decided to take action. He persuaded the Kent committee to cancel the return fixture. Later that season, Crossland was found to have broken his residential qualification for Lancashire by living in Nottinghamshire and Nash dropped out of the side. Thus the two counties resumed playing each other the following season. Harris's Wisden obituarist wrote: "there can be no doubt the action of Lord Harris, even if it did not entirely remove the throwing evil, had a very healthy effect on the game."