Background Synaptic plasticity, which primarily takes place in the hippocampus, is the molecular basis of long- term memory formation. Brain derived neurotrophic factor (BDNF), a member of the neurotrophin family, plays a significant role in synaptic plasticity and memory formation. When BDNF is released, it binds to its receptor and activates various intracellular signal transduction pathways leading to synaptic plasticity. Several methods to improve memory function in humans have been studied, one of which is the use of herbal compounds, such as Centella asiatica (CeA), an herbaceous plant that has been used for improving memory. This study aims to examine the effects of CeA ethanol extract on BDNF protein expression in the CA1 hippocampal region in adult male rats. Methods A randomized experimental design was performed involving 18 adult male Wistar rats. The rats were randomized into three groups: one control/distilled water group and two groups treated with doses of CeA ethanol extract of 300 mg/kgBW (CeA300) and 600 mg/kgBW (CeA600), respectively. CeA ethanol extract was administered orally for 28 consecutive days with weekly weight-adjusted dose. After 28 days, the rats were decapitated, and the hippocampus was isolated from the brain. BDNF protein expression was assessed using immunohistochemistry. Data was analyzed using Kruskal-Wallis test and continued with post-hoc analysis. Results There was a significant increase in BDNF protein expression in the CeA600 group compared to the control group (p<0.001). Conclusion Administration of CeA ethanol extract increased BDNF protein expression in the CA1 hippocampal region of adult male rats.