Early newborn hearing screening allows for early detection of hearing impaired infants, timely diagnosis, early treatment, and promotes language development during the critical period of language learning. Newborn hearing screening is accomplished through electrophysiological techniques such as otoacoustic emission automatic auditory brainstem response and acoustic resistance. The rapid, non-invasive screening is performed in the natural sleep or quiet state of the newborn after birth and the test can be completed in only 5-10 minutes. Preliminary testing is required preferably within 48 hours of birth, and those who do not pass can be retested within 42 days, and those who do not pass the 42-day retest will undergo a diagnostic hearing test at about three months. The principle of the test is that a normal cochlea produces a very soft sound that travels through the auditory chain and tympanic membrane to the ear canal and can be detected, but if the baby has a cochlear hearing impairment, it will not produce otoacoustic emissions and will not be detected by the otoacoustic emission test. If the baby has a cochlear hearing impairment, it will not produce otoacoustic emissions and will not be detected with otoacoustic emissions testing. Generally, when the baby is in deep sleep or at rest, a suitable size probe or earmuff is placed in one of the baby’s ears to start the test and the other side should be tested after the test.