Introduction: In India, 10–15% of all babies are born prematurely, and it accounts for 70–80% of all perinatal deaths. Beta-agonist like Isoxsuprine is widely used to prevent preterm labor, but can sometimes have life-threatening side effects; hence alternative glyceryl trinitrate (GTN) patch is compared with Isoxsuprine for efficacy and safety. Methods: Fifty women of gestation age 28–36 weeks, with two or more uterine contractions every 10 minutes for more than 1 hour but not in active labor with cervical dilations less than 2 cm. were included in the study. Twenty-five women were administered tablet isoxsuprine (duvadilan) 10 mg thrice daily and the rest 25 women received transdermal GTN patch releasing 10 mg per 24 hours. If after 2 hours there was no effect, an additional patch of 10 mg was applied. Time taken for the arrest of contractions, dose required for cessation of contractions, duration of delay in delivery, foetal outcome, APGAR score at birth, and birth weight were recorded for both the groups. Results: Eighty-eight percent achieved successful tocolysis in GTN group as compared to76% in Isoxsuprine group (p = 0.467), while the mean time taken to stop uterine contractions was less in GTN group (4.84 hours) as compared to Isoxsuprine group (7.8 hours) (p = 0.020). Mean gestational age at delivery was 34.97 weeks in the GTN group versus 33.24 weeks in isoxsuprine group (p = 0.004). Fetal outcome and maternal adverse effects was more favorable in the GTN group as compared to Isoxsuprine. Conclusion: Nitroglycerine is well tolerated, noninvasive and convenient therapy for tocolysis, requiring minimal monitoring of mother and fetus as compared to Isoxsuprine.