Experiments were carried out to evaluate the air speed distribution of an enclosed nursery pig bay in summer and winter. The data taken by experiments were compared to validate with the calculated air speeds by a commercial CFD code, FLUENT. Air basically enters into the bay through perforated circular ducts overhanged on the ceiling, leaves through a exhaust fan attached on the end-wall of the bay. Air speeds were measured as 2 ${sim}$ 2.5 mls at the perforated holes in the duct in winter and 7 mls in summer. The validation showed that a CFD simulaton is one of feasible methods to predict airspeed distribution in the nursery pig bay.