Objective In this study， we established an experimental acne model of rabbit ears， observed the histopathological changes of rabbit ear acne， the changes of shin mast cell and the effect of Artemisia volatile oil on acne in model rabbits. Methods 2 percent of coal- tar solution coated on the inner ear in rabbits， after 2 weeks， according to the experimental procedure， the rabbits were randomly divided into Blank control groups、 Matrix groups、 Artemisia volatile oil of high， medium and low concentration groups， 0.025% dimensional A acid cream group， a total of six group. Under the microscope observed the histopathological changes of rabbit ear acne and the changes of shin mast cell. Results After 2 weeks of coal-tar oil， Visible to the naked eye of rabbit ear appear human kind acne change；Under light microscopy show similar pathological changes likes human acne； The number of mast cells increased obviously， after the treatment of Artemisia volatile oil has decreased. Conclusion Artemisia volatile oil has an good effect on the experimental acne， reduced the inflammatory reaction， reduced the number of mast cells. In the treatment of acne the mechanism of Artemisia volatile oil is probably by inhibiting proliferation、 chemotaxis and degranulation of mast cells.