Background Maternal mortality remains unacceptably high in developing countries. One key strategy to reduce such mortality is utilization of birth preparedness and complication readiness (BP/CR) and creating awareness of BP/CR is an important step for pregnant women, their families, and the community. However, there was limited to no evidence regarding the community's awareness on BP/CR in the study area. Therefore, this study aimed to assess knowledge on BP/CR and associated factors among pregnant women in Debremarkos town, Northwest Ethiopia, 2017. Methods A Community based cross-sectional study was conducted from July 1 to 30/2017. A total of 441 pregnant women were included in the study. Structured and pretested questionnaire was administered through face to face interview to collect the data. Simple random sampling technique was used to select the study participants. The data were entered in to Epinfo version 7.0 and then exported to SPSS version 20.0 for analysis. Both bivariate and multivariable logistic regression model were fitted. Crude and adjusted odds ratio with 95 % confidence interval have been computed and variables with p-value < 0.05 were considered statistically significance. Results. The proportion of pregnant women having good knowledge on birth preparedness and complication readiness was found to be 45.2 with 95%CI (40.4, 50.0). In the multivariable analysis, having history of childbirth (AOR=2.17;95%CI:1.18,4.00), having intended pregnancy (AOR=2.13;95%CI: 1.16, 3.90), being governmental employee ( AOR=6.50; 95%CI: 2.50, 16.87), and having Antenatal care visits (AOR=5.50; 95%CI:2.2,13.70) were factors which were independently and significantly associated with good knowledge on birth preparedness and complication readiness. Conclusion Proportion of pregnant women having good knowledge on birth preparedness and complication readiness was low. Putting emphasis on intended pregnancy and antenatal care visit was recommended.