OBJECTIVE. Pompe disease is an autosomal recessive lysosomal storage disorder that is caused by deficient acid α-glucosidase activity and results in progressive, debilitating, and often life-threatening symptoms involving the musculoskeletal, respiratory, and cardiac systems. Recently, enzyme replacement therapy with alglucosidase α has become possible, but the best outcomes in motor function have been achieved when treatment was initiated early. The aim of this study was to test the feasibility of screening newborns in Taiwan for Pompe disease by using a fluorometric enzymatic assay to determine acid α-glucosidase activity in dried blood spots. METHODS. We conducted a large-scale newborn screening pilot program between October 2005 and March 2007. The screening involved measuring acid α-glucosidase activity in dried blood spots of ∼45% of newborns in Taiwan. The unscreened population was monitored as a control. RESULTS. Of the 132 538 newborns screened, 1093 (0.82%) repeat dried blood-spot samples were requested and retested, and 121 (0.091%) newborns were recalled for additional evaluation. Pompe disease was confirmed in 4 newborns. This number was similar to the number of infants who received a diagnosis of Pompe disease in the control group (n = 3); however, newborn screening resulted in an earlier diagnosis of Pompe disease: patients were <1 month old compared with 3 to 6 months old in the control group. CONCLUSIONS. To our knowledge, this is the first large-scale study to show that newborn screening for Pompe disease is feasible. Newborn screening allows for earlier diagnosis of Pompe disease and, thus, for assessment of the value of an earlier start of treatment.