Andorinhas Hill is an integral part of the Serra da Tiririca State Park rocky outcrop complex and is located in the municipality of Niteroi, RJ. The colonization by exotic plants was evaluated based on point-transect and intercept-line techniques. On the main trail, the plants were registered with the GPS aid, and their presence was recorded in two circular plots of five meters on both sides of the trail, at horizontal intervals of 100 m, totaling 19 intervals. Each species cover values were estimated according to Braun-Blanquet scales, considering five classes: C1 (10%), C2 (25%), C3 (50%), C4 (75%) and C5 (100%). In the adjacent tracks, twenty transects were stretched, perpendicularly arranged to the main trail and the line length that was intercepted by each exotic species was taken note. With the obtained values in the two techniques, the phytosociological parameters were calculated. From the point-transect technique 15 invasive species were collected, belonging to 13 families and 15 genus. The species with the highest frequency and coverage values were Megathyrsus maximus, Hibiscus rosa-sinensis, Furcraea foetida e Euphorbia umbellata. In turn, the line intercept technique showed eight species belonging to five families. The species of most importance were F. foetida, Phyllostachys aurea, Oeceoclades maculata, M. maximus e Tradescantia zebrina. Of the exotic species total number, those with invading characteristics are Furcraea foetida, Megathyrsus maximus and Phyllostachys aurea which are cultivated in the surroundings, along the trails and established on the outcrop.