Background: Postpartum family planning is an important intervention for reducing high risk fertility behavior and spacing birth intervals; which ultimately helpful for the health of mothers and their babies. Hence, this study aimed to determine the magnitude of timely initiation of postpartum contraceptive and associated factors among extended postpartum women in Pawe district, Northwest Ethiopia.Methods: Community based cross-sectional study design was employed from February to March 2019 in Pawe district. A stratified multistage sampling technique was used to select a total of 820 women in the extended postpartum period. Data were collected using a pretested interviewer administered questionnaire. A bivariable and multivariable logistic regression model was fitted to identify determinants of timely initiation of postpartum contraceptive among extended postpartum women. Adjusted Odds ratio (AOR) with 95% CI was computed to assess the strength and presence of an association. Variable with less than 0.05 p-value considered as a significant determinant of contraceptive initiation.Results: Out of the total participants about 37.2% [95% CI (34.0, 40.5)] initiated postpartum contraceptive. Time return of menses [AOR=18.32, 95% CI(11.66,28.80)], postnatal care [AOR=7.8, 95%bCI(3.98,15.44)], knowledge level regarding modern contraceptive methods [AOR=3.0, 95% CI(1.40,6.59)], time of resumption of sexual intercourse [AOR=2.1, 95% CI(1.327,3.21), husband approval to use contraceptive [AOR=2.45,95%CI(1.42,4.22), antenatal care [AOR=2.1,95% CI(1.13,3.76), place of delivery at institution [AOR=2.0, 95% CI(1.22,3.39)], and got family planning counseling at delivery [AOR=2.34, 95% CI(1.22,4.49)] were factors associated with timely initiation of postpartum contraceptive. Conclusion and recommendation: The magnitude of timely initiation of postpartum contraceptive was low. This suggests strengthening the integration of postpartum contraceptive use with other basic maternal health services and improving knowledge of women in practicing timely initiation of postpartum contraceptive before engagement to risk activities of unintended pregnancy is important.