Malnutrition has been associated with increased morbidity and mortality. The objective of this study was to determine the nutritional status and micronutrient levels of hospitalized patients in an infectious disease clinic and investigate their association with adverse clinical outcomes. The nutritional status of the study participants was assessed using the Nutritional Risk Screening 2002 (NRS 2002) and micronutrient levels and routine biochemical parameters were tested within the first 24 h of the patient's admission. The incidence of zinc, selenium, thiamine, vitamin B6, vitamin B12 deficiency were 66.7% (n = 40), 46.6% (n = 29), 39.7% (n = 27), 35.3% (n = 24), 14.1% (n = 9), respectively. Selenium levels were significantly higher in patients with urinary tract infections, but lower in soft tissue infections. Copper levels were significantly higher in patients with soft tissue infections. In the Cox regression models, lower albumin, higher serum lactate dehydrogenase levels and higher NRS-2002 scores were associated with increased death. Thiamine, selenium, zinc and vitamin B6 deficiencies but not chromium deficiencies are common in infectious disease clinics. New associations were found between micronutrient levels and infection type and their adverse clinical outcomes. Hypoalbuminemia and a high NRS-2002 score had the greatest accuracy in predicting death, systemic inflammatory response syndrome and sepsis on admission.