This study was aimed to design a linear-capping machine suitable for replacing the bottles frequently. Four heads linear-capping machine was designed with adjusting mechanism and quick replacing mechanism to match bottles with different length, width, high, and caps. Its structure, working principle and the design of adjusting mechanism were also illustrated. Among them, the level adjusting mechanism converted two screw’ s rotation movement into four capping heads’ linear motion, utilizing the principle of the screw mechanism. And the two screws could rotate in special transmission ratio in accordance with the gear ratio. So equal spacing adjustment of four capping heads could be achieved by simply turning the handwheel. And quick replacing mechanism was designed for its capping heads. Four heads linear-capping machine had simple structure, low cost, and convenient adjustment when changing bottle shape, which largely increased the productivity. Four heads linear-capping machine could have more practicability and popularization in the field of packaging machinery.