Background. Delay in the diagnosis and treatment of tuberculosis exacerbates the disease and clinical outcomes. It further enhances transmission of the infection in the society as well as increased the severity of the illness and raised rate of mortality. Objectives. The major goal of this study is to determine the magnitude of delays in tuberculosis treatment and factors affecting tuberculosis treatment among adult tuberculosis patients at Debremarkos town, North West Ethiopia, 2018. Methods. Institution-based cross-sectional study design was employed. Systematically selected 300 adult TB patients were recruited to the study. The study was conducted at Debremarkos town public health facilities from March 1 to April 30, 2018. Logistic regression models were fitted to identify the predicting variables and control confounder’s of the outcome variables. P value ≤ 0.05 with 95% CI was considered as an indicator for the presence of statistically significant association. The result revealed that the median total delay was 23 days (IQR: 19-28 days). The median patient and health system delays were 20 days (IQR: 15-20 days) and 4 days (IQR: 3-5 days), respectively. Tuberculosis patients living in a rural area were 1.14 times more likely to delay for the TB treatment (AOR: 1.141, 95% CI (1.106, 2.608)). Patients who were unable to read and write have almost two times a chance of being delayed (AOR: 2.350, 95% CI (1.630, 2.608)). Monthly income of patients has found another predictor for delay; patients with low monthly income were about six times more likely to delay for TB treatment (AOR: 6.375, 95% CI: (1.733, 23.440)). Those TB patients who had visiting traditional healers before arrival to health facilities were about 2.7 times more likely to delay for TB treatment(AOR: 2.795, 95% CI (1.898, 8.693)). Conclusion and Recommendation. The significant proportion of delays in tuberculosis treatment was found in this study. Living in the rural area, unable to read and write, lower monthly income, and visiting traditional healers were found independent predictors of TB treatment delay. The regional and zonal health administrator shall design various awareness creation mechanisms to educate the public about timely initiation of tuberculosis treatment.