In this study, we demonstrated the effects of CA on BPH in TP-induced BPH rats by measuring the prostate tissue weight, examining the histological changes, and evaluating the major factors involved in the biology of BPH such as prostate specific antigen (PSA), 5AR, AR, SRC1, estrogen receptor α (ERα), and mitogen-activated protein kinases (MAPKs). This evidence concerns the gene ESR1 and benign prostatic hyperplasia.