It is possible that the growth and promotion of online gambling will result in substantially increased use of these types of games in countries where they are legal. This may be especially true for young people due to their interest in such games. In this context, it is important to note that online gambling is more addictive than any other type of game due its structural characteristics, such as immediacy, accessibility, ease of betting, and so on. This study examined the effect of online gambling in Spain 2 years after its legalization. The sample included 1277 pathological gamblers in recovery at 26 gambling addiction treatment centers. Our results showed a significant increase in young pathological gamblers since the legalization of this activity. This is a very relevant issue because, as in the case of Spain, many countries are currently in process of legalization of many types of online games. Scientific research can be useful to adapt the adequate gambling policies in order to prevent the gambling addiction.