The aims of this study were to find out the degree of loneliness among adolescents with immigrant backgrounds in Portugal and the factors that may predict the level of loneliness among them. The study sample consisted of 313 adolescents. The mean duration of sojourn in Portugal for the sample was 8.2 years (SD= 4.8). They were asked to complete a questionnaire. A control group involving 363 Portuguese youth was also included in the study. There were no significant differences between adolescents from immigrant families and Portuguese adolescents who have never migrated in terms of level of loneliness. The strongest predictors of loneliness were self-esteem, duration of sojourn, and perceived discrimination. Implications of the study for counselors are suggested.