Background: Low birth weight among preterm neonates is a crucial public health problem worldwide. Objectives: The study aimed to assess if massage therapy and coconut oil application could affect weight gain in premature neonates. Method: A double-blind, randomized controlled trial (RCT) was conducted in neonatal intensive care units (NICU) of two educational hospitals affiliated with Shahid Beheshti University of Medical Sciences, Tehran, Iran, from September 2019 to April 2021. Massage therapy, alongside applying coconut oil to the skin for five days, versus massage therapy with tepid water, was considered an intervention. Demographic data, weight gain, and serum triglycerides (TG) levels were the outcomes. First, oil was tested on the baby’s wrist skin. If there was no skin reaction or side effects, massage therapy was started using fingertips in 3 steps, and each step lasted for five minutes. Results: The study included 94 neonates with a gestational age of fewer than 37 weeks who were randomly assigned to three groups: body massage with coconut oil group (n = 33), body massage without oil (n = 30), and control group (n = 31) who did not receive any intervention. Fifty-one cases (54.3%) were male. The mean gestational age of all patients was 32.5 ± 2.24 weeks (range of 27 to 36.6), birth weight was 1769.04 ± 472.8 grams (range of 800 to 2780 grams), serum triglycerides levels before and after intervention in all patients were 0.87 ± 0.43 and 1.14 ± 0.50 mmol/L respectively (or 77.04 ± 39.7 and 100.94 ± 44.7 mg/dL respectively) (P = 0.44). The five-day average weight gains based on the groups included: coconut oil: 49.24 ± 94.32 grams, tepid water: 27.16 ± 65.79 grams, control: 26.29 ± 77.09 grams, P = 0.49. There were no statistically significant differences among all groups for weight gain and change in serum TG levels. Conclusions: Massage therapy, alongside applying coconut oil to the skin for five days, could not increase weight and serum TG levels in premature neonates. Further studies with long-term intervention and a larger sample size are recommended.