Guam Highway 3 (GH-3) is one of the primary automobile highways in the United States territory of Guam.

It runs in a south to north direction, from a junction with GH-1 near the Micronesia Mall in the southern community of Tamuning in a general northeasterly direction to the community of Dededo, where it meets GH-3A and GH-9. In between, it passes Naval Computer and Telecommunications Station Guam and the newly-established Marine Corps Base Camp Blaz.

This section is missing mileposts for junctions. Please help by adding them.

Location	mi	km	Destinations	Notes
Tamuning			GH-1	Southern terminus
Gugagon			GH-28
Dededo			GH-3A GH-9	Northern terminus
1.000 mi = 1.609 km; 1.000 km = 0.621 mi

Guam Highway 3A
Location	Tamuning–Dededo

Guam Highway 3A (GH-3A) connects GH-3 and GH-9 to Ritidian Point at the northern tip of the island of Guam in Dededo. It is undergoing expansion to accommodate increased activity from the activation of Camp Blaz.