Introduction: Medicinal plants are often used by community because of all natural, safe and relatively few side effects. Medicinal plants commonly used by Indonesian are swamp cabbage as it potentially generates hypnotic effect and in overcoming the problem of sleep disorders.Objectives: to assess whether the swamp cabbage, have a hypnotic effect with the parameter of time to sleep and sleep duration in the Swiss Webster male mice induced phenobarbital.Methods: This study was based on real experimental using comparatively Completely Randomized Design. Thirty male mice were divided into 5 the group which is given ethanol extract of swamp cabbage 2000 mg /kg bw, 4000 mg /kg bw, 8000 mg /kg bw, comparator (diazepam), and controls (CMC 1% suspension). The measured data is time to sleep and sleep duration in minutes. Analysis of data using one-way test ANOVA followed by Tukey HSD test with α = 0.05, significance based on p ≤ 0.05, using a computer program.Results: The fastest time to sleep is in the group given dose of 8000 mg /kg bw which was 17 minutes followed by the dose of 4000 mg /kg bw and the 2000 mg /kg bw are 24 minutes and 32.3 minutes, respectively. The sleep onset results is in the group given dose of 8000 mg/kg bw and 4000 mg/kg bw are differently significant compared to CMC 1% suspension group with p=0,001 and 0,032, respectively. The longest sleep duration is in the group given dose of 8000 mg /kg bw which is 211.5 minutes followed by the dose of 4000 mg /kg bw and 2000 mg /kg bw are 197 minutes and 157.2 minutes, respectively. The sleep duration results is in the group given dose of 8000 mg/kg bw is differently significant compared to CMC 1% suspension group with p=0,020.Conclusion: Swamp cabbage hasten time to sleep and prolong sleep duration.