To determine the demographic and systemic parameters in children with solid malignancies and to ascertain which of them affected the delay in diagnosis, a retrospective study was performed on 315 children diagnosed with a solid tumor at our hospital, including epidemiological, social, and medical issues concerning the family, the child, the medical system, and the tumor. Lag time, defined as the interval between onset of symptoms and final diagnosis, including parent delay and physician delay, was estimated for each child. Mean lag time: 15.75 weeks (w), median: 7 w, range: 0-208 w. Lowest mean values appeared in kidney tumors, highest in epithelial, brain and soft tissue sarcomas. Mean parent delay: 4.42 w, median: 1 w, range: 0-130 w. Mean physician delay: 11.17 w, median: 4 w, range: 0-206 w. Among the demographic and personal parameters, the best predictors for diagnosis delay were age of child and father's ethnic origin. Several factors influenced diagnosis delay of childhood solid tumors. Recognizing these factors could minimize the delay, thereby improving the child's chances of survival.