Kourou has its own small airport (Kourou Airport, ICAO: SOOK), but scheduled commercial services are limited — the main point of entry for French Guiana is Félix Éboué International Airport near Cayenne, about 65 km southeast. Direct flights connect Cayenne with Paris (Air France, roughly 9 hours), as well as Martinique, Guadeloupe, Fort-de-France, and a handful of other Caribbean and South American destinations.
From Cayenne airport the most common route to Kourou is by shared taxi (taxi collectif), which departs when full from the area outside arrivals. The journey takes about an hour. Private taxis are faster but significantly more expensive, as with everything in French Guiana. A rental car from Cayenne airport is a practical option if you plan to explore more of the territory.
There is no railway. Long-distance buses connect Kourou with Cayenne and Saint-Laurent-du-Maroni to the west, but frequency is low and schedules are irregular.