IntroductionThe processes of life were birth, aging, illness and death. We have suffered from various illnesses in our lives. It was a good reason to be absent from school, work or other daily work activities. However, from a sociologist's perspective, people in the sick role were viewed as having committed a crime and this was treated as deviant behavior (Peter & Meredith, 1998). In the structural-functional model, people took on different tasks and roles in society or in different institutions. These were reliable with the structures and norms of society. Did the disease have any effective element in society? This article describes the concept of the sick role and its application in nursing practice (Parson, 1979). Sick role concept Talcott Parsons (1902 – 1979) was a famous American sociologist and structural functionalist. He developed a general theoretical system for analyzing society. In his theoretical system, people maintain their status and play their role in society, called social role. In his conception, social roles were expected behaviors (including rights and obligations) of anyone who held a certain position in society (Diligio, 2005). This type of social role maintained the structural and functional status of society. I used Mr. Lee as an example to illustrate social roles. Mr Lee was a registered nurse. He lived with his wife and daughter. According to Parsons' theoretical system, Mr. Lee has three social roles. In the hospital, he took on the role of nurse. He took care of his patients. At home, he assumed the role of husband to his wife and father to his daughter. The sick role was first defined by Talcott Parsons (1951) in his seminal work describing a set of behaviors. These behaviors were associated with people becoming seriously ill. As described by Parsons, the sick role is a process in which an individual experiences a change in role identity or role expectations. As a result, people suffered from the disease. Parsons base, there were some members in the sick role. First of all, the disease was involuntary. Second, residents in the sick role were exempted from their usual work; family, civic and permission to “take care” from healthcare workers and others.