Playing to games of chance in their great variety is a very common phenomenon in our western society for a number of reasons. This can lead to an « addiction » when it reaches certain levels, which can have pernicious repercussions in the person, as well as in society. In a particular way, which is of most interest to us, it has repercussions on the conjugal and family life of the addict. The author of this article examines the influence of such addiction on matrimonial consent: in the first instance he describes the psychological and sociological aspects that characterise the addict. Later, starting from the nature of matrimonial consent and existing canonical jurisprudence on the subject, he analyses the repercussions of game addiction on matrimonial consent, the concept of addiction used in jurisprudence and its incidence in the nullity of marriage across a number of grounds: lack of due discretion (can. 1095, n. 3); error in a quality of a person (can. 1097, 2); and deceit (can. 1098). He concludes with a recapitulation of the principle aspects of this question considering both the preventative possibilities and its impact on marriage.