Abstract: The present invention relates to a drum stencil printing system for reliably and automatically printing materials on the inside of a concave surface. The drum stencil printing system includes a pliable drum stencil secured in place by a stencil spring. As the printhead applies radial pressure to the drum stencil, the portion of the stencil in contact with the printhead is deflected to make contact with the container sidewall. When the printhead rotates, the portion of the stencil contacting the container sidewall also rotates to match the nozzle of the printhead. After printing is complete, the printhead retracts, and the pliable stencil is returned to its undeflected position, breaking contact between the stencil and the container, and protecting the printed material from being rubbed or worn off of the container.