A handle assembly for a spinning reel for fishing includes a handle shaft connected to a reel body and having an end projection, and a handle arm connected to the handle shaft. The handle arm is provided with a channel-shaped groove in which the projection of the handle shaft is received. The arm is pivotally connected to the shaft projection, and rotatable between a first position in which it is coaxial with the shaft and a second position in which it is perpendicular to the shaft. The arm is also provided with a recess contiguous to the groove. A slider is slidable in the recess. A spring is disposed in the recess for urging the slider into locking engagement with one side of the shaft projection when the arm is in its first position.