The hypernatremic neonatal dehydration is a severe condition whose incidence has increased in recent years resulting in complications leading to the hospitalization of the newborn.Describe the clinical and laboratory characteristics of term-newborns with Hypernatremic Dehy dration diagnosis.Descriptive observational study of hospitalized term- newborns due to hypernatremic dehydration between a period from 2014 to 2016. Term newborns over 37 weeks with clinical signs of dehydration (dry mucous membranes, depressed fontanel, tear less crying, signs of the cutaneous pleat), and/or excessive weight loss greater than 7% and serum sodium greater than 145 mEq/L were included. Sociodemographic and biochemical variables were recorded for analysis.43 neonates were included. 60.5 percent of their mothers were pri- miparous, 90 percent of neonates received exclusive breastfeeding, mothers reported breastfeeding problems in 76.7 percent. Incoming neonates reported weight loss compared to birth weight at 15.3% on average. 83.3% had public health insurance. 65.1% had dehydration clinical signs at entry and 83.5% transient neurological signs. The average sodium was 155 mEq/L at revenue. The sodium decrease in the first 24 hours of handling was 7.74 mEq/L (0.32mEq/L per hour). The correction of the hypernatremia was 55.8% by oral intake and 4 days hospital stay on average.The feeding's problems came up in a (76%), primiparous mothers in an (88.4%). 90.6 percent of this population administered exclusive breastfeeding, results that can help to alert the health professional to timely identification, warning signs, and early post-discharge control and preventive measures.