Aim and objective: The study was planned to assess the serum zinc levels in children aged 2 months to 5 years admitted with lower respiratory tract infections and to study the association between low zinc levels and other known risk factors for lower respiratory tract infections. Material and Methods: This Case-Control study was done the Department of Pediatric, Anugrah Narayan Magadh Medical College and Hospital, Gaya, Bihar, India for 1 year. Total of 80 cases and 80 controls were enrolled in the study. Detailed General examination was carried out in the patients along with Respiratory system and other systemic examination and a clinical diagnosis was made and entered into the proforma. The details of blood investigations and imaging for confirmation of clinical diagnosis were also noted during the stay of the patient in the hospital. The serum zinc estimation was done by using colorimetric test. Results: The mean age of cases was 1.61±1.32 yrs and that of controls was 1.88±1.71 yrs. The Sex wise distribution of the cases and controls consisted of 51(63.75%) of cases being male and 29(36.25%) being female as compared to 49(61.25%) of controls being male and 31(38.75%) being female. The Mean serum zinc levels in the cases and controls, after comparison, were found to be significantly different (p=0.0001), with mean value for the cases being 59.64 ± 11.82 ug/dl as compared to 84.94 ± 15.83 ug/dl for the controls. A total of 45 cases and controls (28.12%) were found to have deficiency of zinc, of which majority (91.11%) were cases (normal range of 60 to 150 ug/dl). The difference in mean serum zinc levels of cases according to WHO IMNCI grading was statistically significant (p value = 0.0001) with cases belonging to Severe Pneumonia group (Mean = 43.23 ± 6.06 ug/dl) having significantly lower value than that of Pneumonia group (Mean = 66.24 ±7.77 ug/dl). we see serum zinc levels according to oxygen requirements, with cases managed on room air having mean of 65.93 ± 7.73 ug/dl, cases requiring supplemental oxygen by nasal prongs having mean of 61.31 ±10.12 ug/dl and cases requiring mechanical ventilation having mean of 40.88 ±7.07 ug/dl.The serum zinc analysis of patients according to outcome shows significantly lower zinc values (p value = 0.0001) in cases who eventually died due to the ALRTI and its complications (n = 13) as compared to those who got discharged after treatment (n=67). Conclusion: The deficiency of zinc causes the patient to have a more serious form of the disease, requiring patient to be hospitalized for longer duration as well as requiring higher oxygen demands and increasing the chances of mortality by it.