The anemometer is a device for measuring wind speed, which is commonly used for weather applications. Standards for calibration of anemometers, depending on the type of anemometer are different. These anemometers can be calibrated in the open environment and in a certain height which has a good range of wind speed and direction. In the first part of this thesis, a cup anemometer is calibrated in a wind tunnel. Wind tunnel makes a carefully controlled airflow over a model and gets necessary information about its flow field. Wind tunnel is one of the best ways to do empirical research on the science of aerodynamics. The main reason for the design of wind tunnel is to create a uniform air flow with minimum turbulence and no flow angle in test section. For this purpose, anemometer is set under the different tilt angles in the wind tunnel test section and the experiments are accomplished under some specified flow velocity to, achieve its calibration curves. For this purpose, the cup anemometer is tested in 9 different tilt angles and transfer function is obtained at any tilt angle for velocity range of 8 to 30 m/s. To improve air flow quality and decrease of turbulence intensity in the test section, a honeycomb layer and two stages of mechanical grids are inserted in the settling chamber before calibration. To evaluate the flow quality, velocity profile and turbulence intensity are measured by a hot wire. Experimental results show that turbulence intensity reaches to 0.3 percent and flow velocity profile becomes uniform in the test section. After flow quality improvement and cup anemometer calibration, distribution of velocity and turbulence are measured at the cup anemometer by hot wire. Hot wire can measure the instantaneous velocity with high frequency, average velocity, flow disturbances, Reynolds stress, flow temperature, and flow direction. In the second part of the thesis, in order to study anemometer flow field, unsteady numerical simulation based on dynamic mesh in cfx has been done. In the last decade Computational Fluid Dynamics (CFD) as a powerful tool for analyzing the behavior of fluid flow in the system with complex geometry has a significant progress. At the end of this project results of numerical simulation verified by experimental data. Flow investigation near the wake region show that out of the wake region, the average of flow velocity is increased and turbulence intensity is decreased. Keywords : Anemometer, wind tunnel, turbulence, numerical simulation, calibration