In this paper, we present NALP (Navigating Assistant using Laser Pointer), a novel interaction technique for large display presentation control. NALP is based on laser dot detection, track recognition and space segmentation, allowing users to manipulate the presentation software (such as PowerPointTM) directly and freely using any kind of common laser pointer. Demanding users only to sweep the pointer to and fro on display, this technique to a large extent solved the problems caused by hand jitter, latency and detection errors existing in other navigation assistant systems. Report on evaluation experiments shows that when delivering an electronic and interactive presentation with large displays, NALP can effectively meet the need and is preferred over other laser pointer interactive methods.