Many other campgrounds are safe as well, I just cannot say which. for instance: Luquillo Public beach is a fabulous spot to camp and has good facilities but is only safe if there are many people there. In the summer it is too crowded on the weekends and in the winter it is too deserted.. If you are a large group (and not on a summer weekend) it is a wonderful spot to camp and swim.
National Parks of Puerto Rico offers 8 campgrounds. This website describes them all ( in Spanish). They are: Luquillo, Seven Seas, Sun Bay in Vieques, Punta Guilarte in Arroyo, Tres Hermanos in Anasco, Camuy at the Camuy Cave Park, Cerro Gordo in Vega Alta and Maricao. Some of these campgrounds are only open a few days a week.
Departamento de Recursos Naturales y Ambientales ( DRNA) offers campgrounds as well ( you MUST reserve in advance, usually in San Juan).
Toro Negro Reserve. Rio Abajo Reserve. Mona Island can only be reached by boat, which is somewhat expensive, there is no water source on the island. Susua Reserve Near the southwest tip of Puerto Rico. Cambalanche Forest Reserve. Camping is allowed in two areas here, eight trails and a beach nearby. Guajataca Reserve Located on Lake Guajataca, the Guajataca Reserve, 40 walking trails and 25 miles of maintained footpaths. Carite Forest There are two campgrounds within this forest. Lake Carite, located nearby, has family style villas and fishing facilities, as well.
Guilarte Forest Reserve, no camping is allowed only use of the cabins (very musty) which are set among a small eucalyptus forest, no electricity, bare-bones cots and barbecue facilities are available.
US Forest Service gives free permits for camping in the El Yunque National Rainforest ( get your permit before 3 pm). There are no facilities though.
US Fish & Wildlife will NOT give camping permits.
The mountain forests of the Cordillera Central (Central 'mountain' range highest point 4,000+ feet) far from any city offer great camping. These lovely, luscious mountains are cool (down to a minimum of 55 degrees on a cool, damp night; up to 70-75 daytime). The rivers up high are very clean, good for swimming and drinking, good fishing too! The campsite is in the Toro Negro Reserve. (Cabins in Guilarte and Maricao) The (man made) lakes are well stocked with largemouth and peacock bass. People enjoy the fly fishing (also stocked with catfish, sunfish, telapia, sardines). A great nearby day hike is down the steep canyon sides of the San Cristobal Canyon (10 degrees warmer at the bottom, 750' down), a volcanic rift. Stream at the bottom. Get a guide from the town of Aibonito.
The karst area is also fascinating with the worlds third longest underground river and valleys riddled with mogotes. Several adventure tour companies will take you body rafting on the underground river and through caves etc. There are three great campgrounds in this area. Guajataca Reserve, Rio Abajo Reserve, see the forest reserves page for more camping details.
The lighthouse on the southwest tip of PR is in a beautiful area, very dry. The easiest place to camp (and access this varied area with lots of good hiking and beaches) would be in the Susua Reserve.
Mona Island is closed to visitors at this time.
The most popular place to camp is on Culebra Island and many Northerners go there in the winter. ($10. per tent at the office there) Take the ferry from Fajardo or fly. The campground is on the exquisitely beautiful Flamenco Beach. Facilities include 'potable' water (but do not drink it!) and toilets. No concessions, but a trip into town by bus is easy and cheap. It is protected at night, with guards. The ocean, hiking, snorkeling are the best there is. Summer is another story. The atmosphere is chaotic, the ferries are overcrowded and it's a zoo.
Vieques Island has camping at the Balneario Sun Bay with facilities. Whatever you leave in your tent, if you leave for the day, will probably get stolen, but otherwise it is fairly safe to camp there. That is true for all the beaches in Vieques and probably all Puerto Rico as well. Any loose items unguarded will probably be filched.
The amazing thing about the forests of Puerto Rico is their gentleness. There are no poisonous snakes, the few scorpions are not very toxic, but there are 'killer bees' now. In the last 15 years the africanized bees have taken over the native bee population, by and large. Stay away from bee hives. The dangers of the beaches, in terms of camping, is people. There are very few safe beaches at night, in fact the beaches are not safe places to camp at all except where controlled as in Culebra (excellent beach and facility) and Seven Seas.
The popular El Yunque rainforest is prone to problems, but only on the periphery because thieves do not penetrate far into the forest, so it's your car that's vulnerable (and only campers if they are unwise enough to camp near a road or trail) (remember this is a rain forest and very wet) Get your free permits at El Portal on rd#191 before 3pm.