"There have been multiple lazing events involving a high powered laser in the vicinity of N1135.70 EO4303.14," US aviation safety officials said in a Notice to Airmen (NOTAM).
IHS Jane's said the coordinates listed in the NOTAM point to a location 750 meters from the People's Liberation Army Navy base in Djibouti.
"Use extreme caution when transiting near this area," the warning stressed.
The Federal Aviation Administration called the laser activity "unauthorized."
Djibouti is strategically located on the Horn of Africa. The US military also maintains a base in the small country, at Camp Lemonnier. Tokyo and Rome both have a base in Djibouti as well, and France hosts Spanish and German troops at its own base there.
The Chinese navy's base in Djibouti is Beijing's first foreign military base.