The aim of this chapter is to analyse antecedents of search engines use as prepurchase information tools. Firstly, there is a literature review of the factors influencing search engines use in online purchases. Then, there is an empirical analysis of a sample of 650 Spanish E-shoppers. Logistical regression is used to analyse the influence of demographics, surfing behaviour and purchase motivations on willingness to use search engines for E-shopping. Data analysis shows that experience as Internet user and as Internet shopper are negative key drivers of search engine use. Most of the utilitarian shopping motivations analyzed predict comparison shopping behaviour. Demographics are not determinant variables in the use of search engines in online purchases. This research enables companies to know the factors that potentially affect search engine use in E-shopping decisions and the importance of using search engines in their communication campaigns.