Within performed study is analyzed illegal producing, repairing, marketing of firearms (except smooth-bore hunting weapon) or ammunition as well as their theft, as normative modalities of expressing penal illicit referred to art.290 PC RM. Within the meaning of art.290 CP RM marketing of firearms and ammunition assumes sells them under the “contract of sale”. Estrangement called entities under other types of illegal transactions cannot be considered as marketing. Making another interpretation of the term “marketing” has only to neglect the rule stated in para. (2) Article 3 PC RM according to which it is prohibited unfavorable extensive interpretation of criminal law. In the event of unlawful taking of a firearm or ammunition when the perpetrator pays something in return, those committed to be classified as illegal purchase, but not theft.