The validation results of MIPAS temperature, density and water vapour measurements using three different reference datasets is presented. The MIPAS temperature and density profiles have been compared to a statistical falling sphere model and to radiosonde data. The MIPAS water vapour measurements were validated using lidar data. Regarding the MIPAS density profiles, a bias of about -20% compared to the statistical model seems to be present. This is probably related to the fact that no in-flight line-of-sight calibration had been applied to data products generated before13 November 2002. The difference between the MIPAS temperature data and the radiosonde data is within about 2% and does not seem to depend on altitude. Nevertheless, there are indications of a dependency on temperature. Also, there seems to be an underestimation of the temperature by MIPAS for measurements at nighttime. The small dataset however, does not allow us to reach statistical significant conclusions for this topic. MIPAS water vapour measurements could onldy be validated at altitudes below 14 km. A preliminary analysis indicates a systematic underestimation by MIPAS of the water vapour mixing ratio compared to lidar data