Describes experimental investigations of velocity measurements performed on three vane anemometers in steady variable-density flows. Measurements of velocity variations as a function of flow temperature, pressure and humidity were collected by an electronic vane anemometer, a rotating vane anemometer and a deflecting vane anemometer. The study aimed to measure the effects of density changes on velocity measurements taken by the three anemometers and determining how well the available theoretical models correspond to the corrections produced by the experimental data. Finds the results indicate significant effects of temperature and pressure on the velocity measurements acquired by the three anemometers.In general the humidity effects are small,. Draws conclusions. Concludes that the paper may serve as a reference on the correction of velocity measurements acquired by commonly used vane anemometers where flow test conditions of temperature, pressure, humidity and/or density deviate from standard values.KEYWORDS: year 1995, Anemometers, experiment, measuring, accuracy, temperature, pressure, humidity, air flow, comparing