The aim of this article is to analyze the attitude of the Spanish population towards immigration from 1997 to 2007. The information is obtained from the survey of attitudes and opinions regarding immigration in Spain administered by ASEP. The results show that, with the passage of time, an increase in anti-immigrant feelings has taken place. The main variables that explain this increase are on the one hand, the threat defined by the number of perceived immigrants and the loss of national identity, and, on the other hand, the competition for the economic and social resources and the state investment destined to immigration.