Background: Premature and low birth weight (LBW) infants are susceptible to infections including those which are preventable. The coverage of immunization in this subset of babies is poor. The present pilot study was an attempt to identify factors which lead to delay in initiation of immunization in this vulnerable group. The objective of this study was to assess knowledge and practice of initiation of immunization in mothers of low birth weight (<2 Kg) NICU graduates and effect of specific counselling on the practice of immunization. Methods: A prospective pilot study was done between 1st April to 30th June 2016. In the first phase, mothers of LBW and preterm babies were assessed using 2 validated questionnaires on discharge and in High-Risk OPD. In the second phase, a different set of mothers were assessed similarly but counseled specifically by the principal investigator to initiate immunization irrespective of the weight and chronological age. Results were interpreted using the Fischer Exact test, Independent T-test and McNemar.Results: Among 30 babies in the study, 16 (53.33%) were immunized, of which 6 (37.5%) babies had a timely initiation. Birth weight and duration of NICU stay significantly affected the time of initiation of immunization. There was a significant lack of knowledge in mothers of non-immunized babies. When counseled by the primary investigator, 85.8% and 50% of mothers agreed that immunization can be initiated at birth and even if birth weight is less than 2 kg respectively.Conclusions: Immunization initiation was delayed in most of the preterm and low birth weight babies. Post counseling a favorable change was observed in mothers’ knowledge but not practice.