This study aimed to evaluate the effects of dietary supplementation with 2% purslane (Portulaca oleracea L.) extract on growth performance and carcass characteristics of Japanese quails reared under high stocking density conditions. A total of 255 fifteen-day-old quails were randomly allocated into three groups: The control group (low stocking density, 160 cm²/bird, basal diet), the HS0 group (high stocking density, 80 cm²/bird, basal diet), and the HS2 group (high stocking density, 80 cm²/bird, basal diet supplemented with 2% purslane extract). The experiment lasted 28 days. Throughout the study, body weight (BW) and average daily gain (ADG) were not significantly different among the groups (p>0.05). However, feed intake (FI) was significantly lower in the HS2 group during days 29–35 and across the total feeding period (days 15–42) (p<0.05). A significant improvement in feed conversion ratio (FCR) was observed in the HS2 group during the same period (p<0.05). Carcass traits were mostly unaffected, except for gizzard weight, which was significantly different among groups (p<0.05). In conclusion, while purslane extract had no effect on body weight under high stocking density, it improved feed efficiency. These findings indicate that purslane may be a useful natural supplement for enhancing performance in quail production under intensive rearing conditions.