A hand-wearing assembly has a main body and a side mirror mount. The main body is a loop and has a connecting top. The side mirror mount is connected with and stands on the connecting top. The side mirror mount has a mirror face facing a rear end of the connecting top and is capable of being connected with a side mirror. The side mirror mount allows the side mirror to stand above a wrist or a back of a hand. Accordingly, a rider can see a rear sight at ease via the standing side mirror. With a slight movement of the hand, the position of the side mirror is easily adjusted to enable the rider to see all the rear area from all directions, or to check the positions of the following cyclists.