This is a protocol for a Cochrane Review (Intervention). The objectives are as follows:

Primary objectives are to assess the effectiveness and safety of enteral zinc supplementation versus no intervention or placebo on morbidity, growth, and neurodevelopmental development among preterm infants.

Secondary objectives include determining:

• effects of enteral zinc supplementation on morbidities typically seen in preterm infants: bronchopulmonary dysplasia, retinopathy of prematurity, bacterial sepsis, necrotising enterocolitis, and intraventricular haemorrhage;

• which infants would profit the most from enteral zinc supplementation (within predefined subgroups: gestational age, birth weight, types of enteral feeds);

• the optimal dose of zinc supplementation: lower dose versus higher dose; or

• the optimal duration of zinc supplementation: short‐term versus long‐term.