Etil p-metoxycynamate (EPMC) is the second largest compound in Kaempferia galanga L. It contains about 31,36% of the EPMC. EPMC has been reported to have anti-diarrhea and anti-inflammatory effects. The purpose of this research is the use of EPMC as an antagonism by inhibiting a muscarinic acetylcholine 3 receptor (Ach M3) which causes smooth muscle contraction at ileum. Maceration is used to obtain an EPMC extract from Kaempferia galanga L. EPMC are identified using Thin Layer Chromatography with the motion phase toluene ethyl : acetate (19:1). The activity of ileum antagonism against acetylcholine test using ileum of hamster isolated in vitro with a dose of EPMC 100 μM and 200 μM. The results obtained will be processed into the value of pD2 and analyzed statistically using One Way ANOVA and carried out to LSD test using trusted level 95%. The AutoDock device is used as a test In Silico against the Ach M3 receptor. Final results showed that EPMC 100 μM and 200 μM were able to inject the Ach M3 indicated by shifting barriers of hamster ileum contraction curves against the acetylcholine agonist. The pD2 value displayed EPMC 100 μM is 7,1 and 200 μM is 6,98 shifted significantly (p<0,5) against pD2 acetylcholine agonists is 8,16. The value of affinity shows the number -5,2.