International reporting, large-scale assessments and long-term monitoring of forest biodiversity gain a lot of attention, but pose still difficulties to overcome. Some assessments concentrate on a few selected indicators, some on only a fraction of the geographical area and some use data, which are not directly comparable due to different definitions and standards used in national assessments. Joint analysis of the data of different initiatives has not always been possible, and political processes on the selection of criteria and indicators may have received attention instead of the plain assessment. Due to these reasons there is no comprehensive overview of the forest biodiversity and variety of the forests in Europe. Thus, this paper attempts to make justice to forest biodiversity as a multidimensional issue and, furthermore, to the variety of European forests. The paper aims to provide a comprehensive overview of the European forest biodiversity. Subsequent to the assessment of the current state the paper aims to analyse the difficulties and deficiencies related to such assessments, and further to outline improvements and alternatives for the future. A pragmatic approach has been taken so that despite of missing universal definition of biodiversity, non-existing “final” list of biodiversity indicators and lacking “perfect” data, an assessment of European forest biodiversity has been made.