Endogenous hydrogen sulfide (H2S), synthesized by cystathionine β‐synthase (CBS) and cystathionine γ‐lyase (CSE), is a potent vasodilator that can be stimulated by estradiol‐17β (E
2β) in uterine artery (UA) smooth muscle (UASMC) in vivo; however, the underlying mechanisms are unknown. This study tested a hypothesis that E
2β stimulates H
2S biosynthesis by upregulating CBS expression via specific estrogen receptor (ER). Treatment with E
2β stimulated time‐ and concentration‐ dependent CBS and CSE messenger RNA (mRNA) and protein expressions, and H
2S production in cultured primary UASMC isolated from late pregnant ewes, which were blocked by ICI 182,780. Treatment with specific ERα or ERβ agonist mimicked these E
2β‐stimulated responses, which were blocked by specific ERα or ERβ antagonist. Moreover, E
2β activated both
CBS and
CSE promoters and ICI 182,780 blocked the E
2β‐stimulated responses. Thus, E
2β stimulates H
2S production by upregulating CBS and CSE expression via specific ER‐dependent transcription in UASMC in vitro.