The invention discloses an adjustable sizing machine with automatic alarm for broken yarn, which comprises a base, the upper surface of the base is fixedly connected with a sizing box, and the interior of the sizing box is respectively provided with a soaking chamber, a A fluffing chamber, a drying chamber and a winding chamber, the left inner walls of the soaking chamber, the fluffing chamber, the drying chamber and the winding chamber are all provided with a threading opening, and the inner wall of the soaking chamber is fixedly connected with a fixing rod , the lower surface of the fixed rod is fixedly connected with a telescopic tube, and the inner wall of the telescopic tube is provided with a telescopic groove. The adjustable sizing machine with automatic alarm for broken yarn achieves the effect of breaking the alarm when the spinning is soaked. When the spinning is broken, the first spring pops up the upper and lower contacts on the lower surface of the piston. Electric connection, and then prompt the alarm to alarm automatically, thereby achieving the effect of automatic alarm for yarn breakage, saving manual inspection time, improving production efficiency, and achieving the effect of fluffing the spinning yarn.