A large number of students stay in a student dormitory during their studies, where they share a room with a roommate. Sometimes they become roommates with a friend of theirs, but sometimes they post ads on student groups and in those ads state their own characteristics and the characteristics they are looking for in a roommate. Those are often personality traits that form a set of relatively permanent and organized psychological traits and mechanisms within the individual that influence the interactions and adaptations of the individual in his intrapsychic, physical and social environment. The most common personality model is the "Big Five" model, which consists of extraversion, agreeableness, conscientiousness, emotional stability and intellect. The aim of this research was to analyze the content of ads for roommates among the student population in order to determine what characteristics of roommates students consider desirable. Content analysis revealed that participants mostly described themselves using the dimension of agreeableness. Most participants wanted a roommate to have agreeableness personality trait. Women were mostly looking for agreeableness in their roommates and men were mostly looking for conscientiousness in their roommates. More research is needed to gain a better insight into roommates in general in Croatia.