Abstract: The present status, existing problems of biodiversity and measures to be adopted were described in this paper. "Biosafety", which is one of the main subjects discussed in every Contracting Party Congress after ratification of Convention on Biological Diversity was introduced in detail as well. The present status was described from the field of species diversity, genetic diversity and ecosystem diversity, respectively. Biodiversity threatened, endangered and extinguished by natural factors as well as habitat loss, deterioration of environment, hunting and smuggling, overfishing and aquatic breeding, development of hitech, global change and introduction of exotic species caused by human activities, were comprehensively analyzed. In the part of measures to be adopted, not only the approaches of solving the problems existed to date were suggested, but also the experience of industrial countries and international programmes developed were illustrated. The solution of "What is biosafety" and "Why the issue of biosafety have to be emphasized" was given clearly.