In January 2001, while conducting a survey of the tick fauna of the State of Rondônia, Brazil, a rural area within Monte Negro county was visited. On one farm within the county the producer maintained a herd of crossbred swine, Sus scrofa L., that was reared under unconfined conditions, with unrestrained access to the pasture and adjacent native Amazon equatorial forest. Inspection of the swine herd produced a total of 77 ticks collected from eight adult pigs (mean, 9.6 ticks per pig) that were identified as Amblyomma naponense (Packard) (26 males, eight females), A. oblongoguttatum Koch (five males, three females), A. ovale Koch (one female) and A. scalpturatum Neumann (one male). One Amblyomma larva and 32 Amblyomma nymphs also were collected from the pigs. Of these, six nymphs were reared in the laboratory until they reached the adult stage, one being an A. oblongoguttatum female and five being A. scalpturatum females.