A correction tape dispenser has a front cover, a core assembly, an extending-and-retracting mechanism and a rear cover. The core assembly is mounted slidably in the front cover and has a convex portion extending out of the front cover. The extending-and-retracting mechanism selectively drives the core assembly to hold forward or backward. The rear cover is mounted on the front cover. A user pushes the core assembly with the extending-and-retracting mechanism forward to extend the head out of or retract the head into the front cover. Retracting the head prevents dust from accumulating on a correction tape on the head.