Background: Leprosy is a chronic infectious disease caused by Mycobacterium leprae and generally manifest as neurodegenerative disorder which may lead to permanent disability. Whether its prevalence tend to be decreased, new and relaps case, complication such as skin reaction, and disability remain problematic whether in much smaller magnitude. Objective: In this study, we observe the prevalence of subclinical leprosy in population who live with leprosy patients in order to determine the rate of transmission and initiate early treatment for those with subclinical disease as well as providing data for future research. Methods: A cross-sectional study was conducted in dermatology and genital clinic of Sanglah General Hospital from may 2016 to August 2016 which included all patient’ family that agreed to be enrolled. The leprosy status of the sample was evaluated using lateral flow test that detect IgM anti-PGL-1 in the serum. Results: 28 leprosy patients and 73 contact person were enrolled in this study. Among the patients, 21 (75%) were Balinese and 7 (25%) were Javanese. Lateral Flow examination found that almost all results were positive (27; 96.42%) for the patients with just 1 patient showed negative result. Meanwhile, from 73 contact person, 11 appear to be positive (15.06%). Conclusion: lateral flow test was proved to be effective method of detecting M. leprae infection and we found 15.06% of contact person had subclinical leprosy.