Aspects on the biology and ecology of Anastrepha obliqua, at both laboratory and field conditions, are given. Adult emergence occurred between 11 to 22 days, with an average of 17 days of pupation. In the field, atmospheric relative humidity seems to be the main factor affecting adult emergence, and is independent of soil humidity and/or existence of available host fruits. Both fungus and hymenopteran parasitoids determine that a percentage of pupae never hatch, but another population fraction hatches in small numbers through the following months. Water consumption is important for adult survival on A. obliqua, but water is also a mortality factor when it reared under laboratory conditions. This causes a good number of adult drawings in rearing cages. Spiders also represent an important mortality factor under mass rearing conditions. A. obliqua adults show a high degree of polyphagism and feed on different kinds of ripe fruits different from those which are infested by oviposition of the gravid females. This behavior explains why it is possible to capture A. obliqua in traps placed in plantations of fruits infested by Anastrepha species other than A. obliqua. Sexual maturity is reached after 17 days, and the maximum longevity recorded under laboratory conditions, varied from 40 to 53 days, with a similar survival rate in both sexes. Life expectancy was found to be 29 days for males and 31,5 for females. Marked adults released in the fields were recaptured after 58 days, suggesting a longer expectancy than in laboratory. Under captivity, much of the mating courtship seems to be ignored, and copulation takes place with no major problem, lasting about 45 minutes.