Introduction: This study was designed to compare the effectiveness of intravenous morphine with nebulized morphine in pain relief of patients referring to the emergency setting with traumatic musculoskeletal pain. Methods: This randomized, placebo-controlled and double-blind clinical study evaluated 160 patients 18 to 65 years of age with acute traumatic pain, who attended the emergency department during 2019. Subjects were assessed with Numerical Rating Scale based on inclusion and exclusion criteria and randomly divided into two groups. In one group, 80 patients received IV morphine (0.1 mg/kg+5 mL normal saline) plus an equivalent volume of IV placebo. In the second group, 80 patients received nebulized morphine (0.2 mg/kg+5 mL normal saline) plus nebulized placebo. Pain score was monitored in all patients with Numerical Rating Scale before and after intervention at baseline, 15, 30, 45, and 60-minute intervals. Patients’ vital signs and possible adverse events were evaluated in each observation time points. Finally, all participants were assessed for their satisfaction with pain management. Data were analyzed using repeated measure analysis for continuous variables and Binomial test for categorical variables Results: There was no significant difference between the demographic characteristics of patients in study groups. Pain relief between the two groups was similar during the observation (0, 15, 30, 45, 60 min) (P>0.05). There were no changes in vital signs between two groups, although the nebulized group had lower systolic blood pressure at the time-point of 15 minutes after the treatment initiation (P=0.03). Conclusion: Although Nebulized morphine has similar efficacy in comparison with IV route, nebulization might be considered as the clinically efficacious route of morphine administration with minimal side effects, providing optimal pain relief in patients.