This paper presents a case-report of cutaneous actinomycosis due to Actinomyces viscosus in a 22 year old man, hospital staff from Tehran with multiple fistulous tracts in his right hand and a history of skin injury due to thorn of plant. Diagnosis was based on the observation of gram positive coccoid, diphtheroid and long branching filaments in direct examination of pus from fistulous tracts and isolation of microorganism in thioglycolate and Brain Heart Infusion (BHI) agar media in anaerobic conditions and some physiologic tests. Treatment of lesion was down with doxycyclin and penicillin 3 months and healing was acquired.