Sleep quality is an important factor that affects infant growth and development. Sleep disturbances are common among infants and may negatively affect physical growth and neurological development. Baby massage and baby gym are non-pharmacological stimulation methods believed to improve infant sleep quality; however, evidence comparing their effectiveness remains limited. This study aimed to compare the effectiveness of baby massage and baby gym in improving the sleep quality of infants aged 3–6 months at Ravina Medika Clinic in 2026. A quantitative approach with a quasi-experimental design using a pretest–posttest two-group design was employed.The study was conducted at Ravina Medika Clinic, Purwakarta, from January to February 2026. A total of 40 infants aged 3–6 months were selected using purposive sampling and divided into two groups: the baby massage group (n=20) and the baby gym group (n=20). Sleep quality was assessed using the Brief Infant Sleep Questionnaire (BISQ) before and after the intervention. Data were analyzed using descriptive and inferential statistics, namely the Wilcoxon Signed-Rank Test and Mann–Whitney U Test, with a significance level of α=0.05.Before the intervention, the majority of infants had poor sleep quality, accounting for 70.0% in the baby massage group and 50.0% in the baby gym group. After the intervention, sleep quality improved in both groups. The Wilcoxon test showed that both baby massage and baby gym significantly improved infant sleep quality (p<0.05). The Mann–Whitney test demonstrated a significant difference between the two groups (p=0.000; p<0.05). The baby massage group had a higher mean rank than the baby gym group; therefore, baby massage was considered more effective in improving the sleep quality of infants aged 3–6 months.