Abstract. All of people who don’t know how to use a computer have heard a bout viruses through programs such as hackers and some means like that. There is no doubt that our culture is fascinated by the potential danger of these viruses. Computer virus have become threat to computer users and almost every field in the advance technology industrial nowadays. Know about virus is very necessary for anti-virus researchers as well as operating systems makers. With the development of the open source systems today, computer viruses on these systems should be considered strictly. The goal of this paper is to present my concept of classification virus computer in UNIX environment. This paper provides some subjective comments on some of the most widely known environment and some methods available to protect UNIX today. propose some viruses that can work on this environment and suggest some methods to prevent as well as restrain damages of these viruses.