We interested on evaluation the effect of NIMV and NCPAP as the first treatment of RDS and then comparing the obtained results. Finally we hypothesized that initial treatment with NIMV in preterm neonates with RDS may obtain more favorable outcomes in terms of the duration of treatment and the endotracheal tube ventilation in comparison to ‘early NCPAP’. In this single-center randomized control trial (RCT) study, infants who will born with a birth weight (BW) =<1500 gr (VLBW) and clinical evidence of respiratory distress will eligible for participation in the study. Infants will exclude if there is any of the following cases: major congenital anomalies, asphyxia, congenital cyanotic heart disease, cardiovascular instability, orofacial anomalies and consent refuse or not provide. Studied neonates will randomly allocate to initial treatment with either early-NIMV (NIMV group) or early-NCPAP (NCPAP group). For infants in early-NIMV group (non-synchronized mode), NIMV will set at peak inspiratory pressure (PIP) of 16 -20 cmH2O (according to infant’s birth weight and chest wall expansion), positive end expiratory pressure (PEEP) of 5 to 6 cmH2O, rate of 40- 50 breaths/min (according to PaCO2), inspiratory time (Ti) of 0.4 seconds and flow rate of 8 to 10 L/minute. NCPAP will initiate on a continuous pressure of 5 to 6 cmH2O with a flow of 8 to 10 L/minute. Surfactant [(100 mg/kg per dose will administered if studied neonates, to keep the SPO2 of > 88% - 92%, need a fraction of inspired oxygen (FIO2) of > 30%. INSURE approach, only as rescue therapy, will use in both groups. Infants on NIMV will wean from a PIP of 14-15 cmH2O, PEEP 4-5 cmH2O, and FIO2 of < 30%, with acceptable clinical evidence and ABG. Infants on NCPAP will wean from a CPAP of 4 cmH2O and FIO2 of < 30%, with acceptable clinical evidence and ABG. After weaning, infants in both groups could be wean to Humidified High-Flow Nasal Cannula (HHFNC) at 2.5 -3 L/min. Efforts to wean the flow by as much as tolerated will make gradually. HHFNC will stop completely once infants will be able to maintain SPO2 between 88-92% in room air for at least more than 4 hours. The primary outcomes of the study are the effect of NIMV on need for intubation/endotracheal tube ventilation (e.g. failure of noninvasive respiratory support) within the first 48 h of study and on the duration of non-invasive respiratory support in each group. Presence of any or more of the following will regard as criteria for failure, in both groups: PH < 7.2 and PCo2 > 60, SPO2 of < 88% with a FIO2 of >= 70% , recurrent apnea > 3 times per hour requiring tactile stimulation and any sever apnea which need to bag and mask ventilation. Secondary outcomes are need to INSURE approach, the duration of dependency to oxygen, incidence of CLD, time to full enteral feeds, length of hospital stay, pneumothorax and other morbidity during the hospitalization such as intraventricular hemorrhage (IVH), patent ductus arteriosus (PDA).