<h4>Background</h4>Chronic pancreatitis is the most common etiology of pancreaticopleural fistula (PPF) in children, and underlying genetic variations are now widely known, accounting for most chronic pediatric pancreatitis.<h4>Case report</h4>We describe a case of previously undetected chronic pancreatitis and PPF with a <i>SPINK1</i> variation in a 10-year-old Thai boy who presented with massive left pleural effusion. This evidence concerns the gene SPINK1 and Pleural effusion.