Abstrak Angka putus berobat dari tahun 2014 hingga 2016 masing-masing angka sebesar 13,9%; 3,40% (13 kasus); dan 6,54% (14 kasus). Tujuan penelitian ini adalah untuk mengetahui determinan kejadian putus berobat penderita TB Paru di Balkesmas Wilayah Semarang. Jenis penelitian ini adalah penelitian observasional analitik dengan rancangan penelitian case control. Kasus didefinisikan penderita putus berobat Tuberkulosis yang berumur 15 tahun keatas dan tercatat pernah menjadi pasien Balkesmas Wilayah Semarang. Kontrol didefinisikan penderita Tuberkulosis yang sembuh atau pengobatan lengkap, berusia 15 tahun keatas dan tercatat pernah menjadi pasien Balkesmas Wilayah Semarang. Sampel sebesar 23 kasus dan 23 kontrol teknik purposive sampling. Penelitian ini menggunakan instrumen yakni kuesioner. Data dianalisis dengan menggunakan uji chi square. Hasil penelitian menunjukkan bahwa motivasi penderita rendah (p value 0,046) dan sedang (p-value 0,004), motivasi keluarga rendah (p-value 0,03), serta efek samping OAT berat (p-value 0,01) dan ringan (p-value 0,04) berhubungan terhadap kejadian putus berobat penderita TB Paru. Sedangkan biaya kesehatan, waktu tempuh, peran PMO , dan sikap petugas kesehatan tidak berhubungan terhadap kejadian putus berobat penderita TB Paru. Simpulan penelitian ini terdapat hubungan antara motivasi penderita, motivasi keluarga yang rendah, dan efek samping OAT terhadap kejadian putus berobat penderita TB Paru di Balkesmas wilayah Semarang. Maka perlu disarankan adanya monitoring efek samping pelayanan kesehatan kepada penderita selama masa pengobatan. Abstract The drop out rate for treatment from 2014 to 2016 was 13.9%; 3.40% (13 cases); and 6.54% (14 cases). The purpose of this study was to determine the occurrence of treatment of patients with pulmonary TB at the Balkesmas Semarang. This type of research is an analytic observational research by arranging research case controls. Cases defined by treatment for tuberculosis were carried out 15 years and above and were recorded as patients of Balkesmas Semarang Region. Control of Tuberculosis patients who have recovered or fully recovered, namely 15 years and above and pregnant patients Balkesmas Semarang Region. Samples were 23 cases and 23 controls using purposive sampling technique. This study uses an instrument namely a questionnaire. Data were analyzed using the chi square test. The results showed that patient motivation was low (p value 0.046) and moderate (p-value 0.004), family motivation was low (p-value 0.03), and side effects were severe (p-value 0.01) and mild (p -value of 0.04) Relation to treatment withdrawal in patients with pulmonary TB. While health costs, travel time , role of PMO, and attitudes of health workers (p-value) were not related to the drop out of treatment for patients with pulmonary TB. The conclusions of the study are the relationship between motivation, low family, and side effects on the drop out of treatment for pulmonary TB patients in the Balkesmas Semarang area. Then it is necessary to read monitoring the side effects of health services until the treatment period.