Abstract Background: Neonatal ventilator associated pneumonia (NVAP) is a major hospital-acquired infection in acute care settings, associated with high mortality and poor outcome. Myeloid cell trigger receptor-1 (TREM-1) is a member of the immunoglobulin super receptor family mainly expressed on the surface of myeloid cells such as neutrophils and monocytes/ macrophages. Soluble TREM- 1 (sTREM-1), is a TREM-1 sub-type that has been reported as a novel and strong indicator of pneumonia. Aim of Study: The Primary objective is to assess the value of sTREM- las a diagnostic and a prognostic marker in NVAP and the Secondary Objective is to compare between sTREM-1 and CRP specificity and sensitivity. Subjects and Methods: This was a case-control study in the NICU at Children's Hospital, Ain Shams University, Cairo, Egypt (6 months duration). This study was carried out on 50 cases devided into two groups each included 25 cases: Group A: Ventilator associated pneumonia (VAP) in neonates (cases). Group B: Age and sex matched neonates diagnosed with res-piratory distress syndrome other than pneumonia and not ven-tilated (controls). The randomization was based on odd or even numbers of patient files number. Result: Regarding Day 1 sTREM-1, AUC was 0.942, Cut-off value was 112.55, Sensitivity was 92% and Specificity was 16%. Regarding Day 4 sTREM-1, AUC was 0.931, Cutoff val-ue was 123.8, Sensitivity was 88% and Specificity was 80%. Regarding Day 1 CRP, AUC was 0.534, Cutoff value was 3.9, Sensitivity was 64% and Specificity was 44%. Regarding Day 4 CRP, AUC was 0.640, Cutoff value was 4.7, Sensitivity was 68% and Specificity was 40%. Conclusion: sTREM-1 is as a diagnostic and prognostic in-dicator in ventilator-associated pneumonia for newborn. Com-parison of sTREM-1 and C-reactive protein in terms of accura-cy and sensitivity. STREM-1 has shown it to be more specific and sensitive than C-reactive protein (CRP).