Nut clamping piece capable of being installed quickly and bolt assembly

The utility model discloses a nut clamping piece capable of being installed quickly. The nut clamping piece comprises a main clamping piece body provided with a threaded hole, an auxiliary clamping piece body with a through hole corresponding to the threaded hole, and a bolt maintaining structure arranged at the position of the through hole of the auxiliary clamping piece. The nut clamping piece can be installed with parts such as a bolt and a gasket together. During the processes of transporting and installing, the nut clamping piece cannot be separated and disengaged, cannot occupy clamping space between the main clamping piece body and the auxiliary clamping piece body, and can achieve quick installation. After the nut clamping piece is installed and fixed, the bolt maintaining structure can also play a role in preventing looseness, and therefore reliability of threaded connection is guaranteed. The utility model further discloses a bolt assembly provided with the nut clamping piece.