Introduction: A study to assess the knowledge on legal and ethical issues in nursing among B.Sc. (Nursing) III year students, College of nursing, Madurai medical college, Madurai. Objectives:  (1)To assess the knowledge on legal and ethical issues in nursing among B.Sc. (N) III year students, (2) To find out the association of knowledge on legal and ethical issues in nursing among B.Sc (N) III-year students with selected demographic variable. Design: The design used for the study was descriptive study design. Subjects: Third year B.Sc. nursing students studying in college of nursing, Madurai medical college, Madurai and who fulfills the inclusion criteria. Sample size: The total sample size is 42 Third year B.Sc. nursing students of college of nursing, Madurai medical college, Madurai. Data collection tool: The tool used to measure the knowledge level was knowledge structured questionnaire. Conceptual framework: The conceptual frame work for this study based on modified health belief model by Rosen Stock and Kegels in 1950. Results: The knowledge on legal and ethical issues in nursing among B.Sc. (Nursing) III-year students shows that out of 42 students, 71% had moderate knowledge and 29% had adequate knowledge. Conclusion: There is a significant  association(p>0.05) between the religion, students education, education of father, occupation of the mother, family income, source of information about legal and ethical issues, reason for doing B.Sc. (N) and the  knowledge on Legal and ethical issues in nursing among B.sc(Nursing)-III year students.