Objectives To study prevalence changes of self-reported pain, sleep problems, and fatigue among 8-year-old children, and to examine the co-occurrence and associated psychosocial variables of these symptoms. Methods 3 cross-sectional representative samples were compared in 1989, 1999, and 2005. The frequency of headache, abdominal pain, other pains, sleep problems, and fatigue were studied. In addition, sociodemographic information and child’s psychiatric problems were inquired. Results The prevalence of abdominal pain, sleep problems, and fatigue, in addition to headache in boys and other pains in girls increased significantly (p < .05) from 1989 to 2005, with cumulative odds ratio (95% confidence intervals) varying from 1.6 (1.2–2.1) to 2.4 (1.7–3.3). All symptoms were associated with each other and with the child’s psychiatric problems. However, psychiatric problems did not explain the observed increase in the symptom frequencies. Conclusions Finnish children’s self-reported pain, sleep problems, and fatigue have increased remarkably. Studies providing information on the causes and prevention possibilities are warranted.