A pivotal hinge has a seat and a shaft, and a first end of the shaft is inserted into the seat. A second end of the shaft is inserted into multiple washers, a first and a second positioning ring, multiple elastic rings and a cushion ring in turn. The first positioning ring can be positioned relative to the second positioning ring and with the friction force of the washers, the excellent position effect can be achieved. Hence, a cover of a laptop computer can be positioned to the chassis of the laptop computer at a desired height.