Objective To study the efficacy of transcutaneous prostaglandin E 1( PGE 1) cream in relaxing the vascular spasm in rabbits, to find an ideal vascular dilation drug. Methods Sixty rabbits were randomly divided into six groups:experiment group 1(using 0.1% transcutaneous PGE 1 cream),experiment group 2(using 0.2% transcutaneous PGE 1 cream),experiment group 3(using 0.4% transcutaneous PGE 1 cream), experiment group 4( using 0.8% transcutaneous PGE 1 cream),PGE 1 control group (without using transcutaneous PGE 1 cream, but using PGE 1 cream only),control group(withous using PGE 1). 0.1% adrenlin was injected to the root of the rabbite ear to induce a model of vascular spasm. After a typical vascular spasm appeared,transcutaneou PGE 1 cream or PGE 1 cream was used on the skin of the ear. The vascular diameter and blood folw rate of the ear were determined before adrenalin injection, 10min after vascular spasm and 10,15,30,60,90 and 120 min after the drugs were used. Results The vascular diameters and blood flow rate were recovered to the levels of before adrenalin injection in experimental group 3, 4 after topical used of transcutaneous PGE 1 cream, and those parameters were significamly increased compared with other 4 groups(P0.05). Conclusions Tramscutameou PGE 1 cream can effectively relax the vascular spasm caused be adrenalin injection.The effect of vascular dilation is related to the dosage of the drug. Transcutaneous PGE 1 cream as a topical vascular dilation drug has advantages snch as wide indications,taking effect quick and enduring, and less side effect. So it might be a new simple, safe and effective drug for the treatment of vascular spasm.