The goal of this article is to map out attitudes towards animal experimentation in Europe (EU15 plus Switzerland), more specifically, to document the current attitudes, perform cross-national comparison of the trends of attitudes towards animal experimentation and of the explanatory factors of these attitudes. We assume that the conception of nature and science influences the perception of animal research. This study analyses a series of surveys that measure European public attitudes towards science and technology, the Eurobarometer (EB) 2001 and 2005. The majority of European countries refused animal experimentation in 2005 and we observe downward trend in every country, except Belgium and Spain. If the trend is similar among the countries the patterns of explanation of these attitudes are quite heterogeneous. Attitudes towards animal testing are explained in every country by attitudes towards science and nature, and by sociodemographic variables (except in Spain and Austria), and in very few countries by scientific knowledge (Belgium) or by values (Sweden and Switzerland). These results may have consequences for science and contribute therefore to the public understanding of science (PUS) research.