Introduction: The postnatal period starts from one hour after the birth of placenta and ends 42 days. The days and weeks following childbirth, the postnatal period, is a critical phase in the lives of mothers and newborn babies. Most maternal and infant deaths occur during this time. Yet, this is the most neglected period for the provision of quality care. OBJECTIVE: The aim of this study was to identify determinant factors of postnatal care in Gonji kolela Woreda, West Gojjam zone, Amhara Region, North West Ethiopia, 2016 METHODS: A community based unmatched case control study design was employed from Jan, 2017 to April 2017 in Gonji kolela woreda West Gojam, Amhara region.500 mothers (167 case and 333 controls) who delivered in the past 1 year residing in Gonji kolela Woreda who were selected from the study population using multistage sampling with simple random sampling techniques were included in the study. A Case: A woman who resided in Gonji kolela district and gave birth from Jan 2016 to Dec 2016 and attended at least one post natal visit after delivery. A control: A woman who resided in Gonji kolela district and gave birth from Jan 2016 to Dec 2016 who did not attend post natal visit after delivery. Data on determinant factors were collected by interview method using structured Questionnaire. Bivariable logistic regression and multivariable logistic regression were used for the analysis. Data were entered cleared and edited using EPI-info software 3.5.1and exported to SPSS version 20 statistical package for further analysis. Result: Mothers having information on PNC were 6.713 times more likely to attend PNC as compared to mothers who have no information on PNC [AOR=6.713,95%CI:(3.814-11.817)]. Mothers who were counseled to return back to health institution were 6.203 times more likely to attend PNC as compared to those who didn’t get the advice [AOR=6.203,95%CI:(3.500-10.993)]. Mothers who have transportation means were 4.965 times more likely to attend PNC as compared to those mothers who didn’t access[AOR=4.965,95%CI:(2.798-8.810)]. Conclusion and Recommendation: The determinants factors for postnatal care were mothers information on postnatal care, availability of transportation and counseling received to comeback for PNC. Health professionals during the post partum period should strength to give intensive counseling for mothers to come back for postnatal service. Health care providers at community level should give information about postnatal care utilization as well as the importance of postnatal care utilization for the mother and neonate.