In recent years, the number of diseases included in newborn screening (NBS) tests has increased rapidly, led by the development of both technology and treatments. Many neurometabolic diseases can now be screened, but direct involvement of the brain, especially in the severe forms of these diseases, causes challenges in NBS. For example, differentiating between neuropathic and nonneuropathic types of disease is difficult but critical because the treatments used can differ. For many diseases with neurological manifestations, the long-term outcomes of new treatments and the influence of NBS are both unclear. In this review, we introduce the "new" NBS test using data from the Screening Center at National Taiwan University as an example. Subsequently, we explore the current challenges in NBS for several neurometabolic diseases.