Objective To examine if children who suffer from significant Nighttime Fears (NF) experience higher degree of general fears and behavioral problems and to explore whether effortful control mediates NF association with internalizing problems. Methods One-hundred and nine preschool children (64 boys) between the ages 4 and 6 years suffering from significant NF and 30 healthy children (16 boys) were evaluated using parental reports of behavioral problems [Child Behavior Checklist (CBCL)], parental and child report of fears [Fear Survey Revised for Parents (FSS-PC), Koala Fear Questionnaire (KFQ)], and a measure of effortful control derived from the Child Behavior Questionnaire (CBQ). Results Children with severe NF also suffer from an increased level of a wide variety of fears other than NF, and exhibit more behavioral problems than controls both on parental and children's measures of general fears, and main CBCL scale scores (Internalizing, Externalizing, Total score). Additionally, children with NF had lower abilities of effortful control (as manifested in CBQ attention and inhibitory control scales). Attention control mediated NF association to internalizing problems scale. Conclusions NF may serve as a marker for anxiety vulnerability, and this vulnerability might be mediated by abnormal attentional control. Our finding also highlights the need for a more comprehensive assessment of behavioral problems, fears and anxiety phenomena among children referred with NF.