The invention discloses a rotor spinning melange yarn forming method and device and product. On a rotor spinning machine, two or more fiber strips enter a feeding mechanism through a striping gate and a horn mouth, the feeding mechanism contains at least two independently controlled feeding rollers and can control the independent feeding of at least two fiber strips, different fiber strips are of different colors, or of different color combinations, or of different fiber components, the feeding speed of each fiber strip is controllable, the feeding can be conducted at different time sections, and the feeding speeds of all the fiber strips are independently changeable or simultaneously changeable; through the implement of continuous constant-speed feeding or segmentation variable speed feeding of different fiber strips, continuous constant feeding or segmentation variable feeding of the fiber strips is controlled; the fed fiber strips break away from a combing roller, are transferred to a delivery pipe, and then enter a spinning cup depending on the centrifugal force of the combing roller and the action of added air flow after the opening and carding actions of the combing roller; single fibers of different components are mixed, condensed and twisted in the spinning cup to form rotor spinning melange yarn blended by monochrome or polychromatic fiber, or with segmentation color effect, uniform linear density or changing linear density.