Background: Preterm infants with bronchopulmonary dysplasia (BPD) are at risk of pulmonary hypertension (PH), a devastating condition which could lead to right heart failure and mortality. <!–[endif]—->(Hilgendorff et al., 2016) It has been reported that versican, an extracellular proteoglycan, was accumulated in vascular lesions in PH in adults. <!–[endif]—->(Chang et al., 2016) The aim of this study is to test whether versican could be a potential biomarker for prematurity-related PH.<!–![endif]—-><!–![endif]—-> <!–[endif]—-><!–[endif]—-> Methods: This is a prospective study conducted in the neonatal intensive care unit at Chang Gung Memorial Hospital during 2017-2018. The study was approved by the institutional human research ethics committee (Chang Gung Medical Foundation Institutional Review Board, Taoyuan, Taiwan). Written informed consent was obtained from all parents prior to the study procedure. The preterm infants who were born at less than 32 weeks of gestational age were enrolled. Serum samples were collected at one week of life, one month of age, the time when signs of pulmonary hypertension developed, and at postmenstrual age (PMA) 36 weeks. At each time point, an echocardiography was performed by a pediatric cardiologist. The diagnosis of PH was made by the clinical presentation and echocardiography. Demographic data and clinical characteristics were documented and analyzed. Serum versican level was quantified by an enzyme-linked immunosorbent assay. Results: Seventy infants were enrolled in this prospective study. The median (interquartile range) gestational age was 28.8 (26.2-30.1) weeks and median birth body weight was 953 (749-1440) grams. Forty-two infants developed BPD. Eight (11.4%) infants had signs of PH before PMA 36 weeks, and three (4.3%) infants had signs of PH after PMA 40 weeks. Serum versican level was significantly higher in infants with PH (mean + SD = 1207 + 227 ng/mL) compared to the same age of infants without PH (mean + SD = 908.6 + 199.7 ng/mL), p < 0.001 by Mann-Whitney test. There were no differences in serum versican level between infants with BPD and without BPD. Conclusion: Versican expression is increased in prematurity-related pulmonary hypertension. The underlying mechanisms need to be further investigated. <!–![endif]—-><!–![endif]—->