Abstract: AimTo study the effect of crocin on intracellular calcium concentration (［Ca²⁺］_i) in cultured bovine aortic smooth muscle cells (BASMCs). MethodsCells were loaded with fluorescence probe Fluo-3/AM and ［Ca²⁺］_i was measured by laser scanning confocal microscope (LSCM). Results In the presence or absence of extracellular Ca²⁺, crocin (1×10^-8, 1×10^-7, 1×10^-6 mol·L^-1) concentration-dependently inhibited the ［Ca²⁺］_i elevation induced by 1×10^-2mol·L^-1 H₂O₂ (for the former, the inhibition rates were 34.1%, 57.1% and 74.3% ,while for the latter were 26.2%, 32.1%, 50.0%). In the absence of extracellular Ca²⁺, crocin (1×10^-8, 1×10^-7, 1×10^-6 mol·L^-1) could inhibit the ［Ca²⁺］_i elevation induced by 70 mmol·L^-1 CHCl₃, the inhibition rates were 27.8%, 27.8% and 50.0% respectively. ConclusionCrocin could inhibit the extracellular Ca²⁺ influx and release of intracellular Ca²⁺ stores in endoplasmic reticulum.