Community’s perception toward mental illness is a major determinant of stigma and discrimination toward mental illness, ignorance, delayed help-seeking attitude, and treatment options. Conceptions of mental illness are often influenced by sociocultural structures and health literacy among communities. Despite the increased burden of mental health problems, little is known about knowledge and perception of the public toward mental illness in rural communities in Sri Lanka. A community-based qualitative study was conducted in a rural, agricultural community in the district of Anuradhapura, in North-Central province of Sri Lanka to explore perception and attitudes toward mental illness. Eight individual, in-depth, semi-structured interviews and one group interview were conducted among a convenient sample of 15 lay community members. The data were analyzed using qualitative content analysis method. Participants described their views and perceptions toward conceptualizing mental illness under four themes, namely, causes of mental illness, complementary treatment methods, stigma and social discrimination, and supporting factors for mental well-being. Poverty, bad relationships, and beliefs influenced by sociocultural and religious background were considered as the main causes of mental illness. Misconceptions, stigma, and discrimination of mentally ill people and their families delayed help-seeking behavior and caused barriers to mental health-care provision. There is a strong need for increasing mental health literacy and awareness among people in rural communities. People’s sociocultural and religious beliefs should take into account when caring for mentally ill people and their family members.