Stress is a change condition caused by severe demands, and it occurs at all ages, depending on responsibility as adults. Furthermore, lavender and rosemary aromatherapy can be used to alleviate the effects. Therefore, this study aimed to compare the effectiveness of lavender and rosemary aromatherapy in managing stress in adults. This was a quasi-experimental two-group pre-post test design study conducted in May 2021. A total of 70 adult subjects were selected through purposive sampling, divided into two groups: one receiving lavender and the other rosemary aromatherapy interventions for 7 days. The stress level was measured by the Depression, Anxiety, and Stress Scale 42 (DASS-42) questionnaire. The results showed average stress before the administration of lavender on the subjects from the first group to be 23.5, after which it was observed to decrease by 8.97%, 18.90%, and 34.14% on the third, fifth, and seventh day, respectively. Meanwhile, in the second group, the average stress before the given intervention of rosemary aromatherapy was 22.14, which was observed to decrease by 12.91%, 25.36%, and 51.14% on the third, fifth, and seventh day, respectively. The Mann-Whitney U test showed a higher reduction in stress levels (p=0.000) after using rosemary aromatherapy. It is concluded that rosemary aromatherapy is more effective (p=0.000) in reducing stress in adults than in lavender.