One of the most fundamental factors related to psychological well being across the lifespan is whether a person perceives social support from important others in his or her life. The current study explored changes in and relationships among perceived social support (SS) and socioemotional adjustment (SEA) across the 1-year transition from elementary to junior high school. Two cohorts of students (N = 140) participated in the current study that took place across a 3-year time span. Analyses of the transition data for boys and girls together reveal declines in perceived total support and teacher support as well as an increase in self-reported school problems. When considering the sexes separately, girls' perceived total support, close friend support and school support declined while boy's self-reported school problems increased across the transition. Although social support did not emerge as a mediator or predictor for any of the socioemotional variables in the current study, results reveal that, in general, perceived social support and socioemotional functioning at the end of the last year of elementary school predicts perceived social support and socioemotional functioning at the end of the first year of junior high school. Study limitations and implications for research and practice are discussed.