Abstract: Physiological parameter monitoring is essential to medical staff to evaluate, diagnose and treat patients in neonatal intensive care unit (NICU). Monitoring in NICU includes basic vital signal monitoring and functional monitoring. Basic vital signal monitoring (including ECG, respiration, SpO2, blood pressure, temperature) is advanced and focus on study of usability, continuity and anti-interference. Functional monitoring (including respiratory function, circulatory function, cerebral function) still focus on study of monitoring precision and reliability. Meanwhile, video monitoring and artifact intelligence have presented well performance on improving monitoring precision and anti-interference. In this article, the main parameters and relevant measurement technology for monitoring critical neonates were described.