Selective serotonin re-uptake inhibitors (SSRIs) are commonly used in the clinical practice of child and adolescent psychiatry because of reasonable safety and tolerability. In the literature, extrapyramidal system symptoms (EPS) induced by SSRI use are more frequently reported in adults, but are rarely reported in children. In this report, we report acute cervical dystonia that occurs due to sertraline dose increase and does not recur after dose reduction in a 12-year-old adolescent girl. Although sertraline-induced cervical dystonia in children and adolescents has been reported as several case reports, our case is the first case occurring on the first day after a dose increase. [Anadolu Psikiyatri Derg 2019; 20(6.000): 667-669]