Objective Severe preeclampsia/eclampsia is a multi-systemic disorder of pregnancy occurring after 20 weeks of gestation associated with significant maternal morbidity and mortality worldwide. The study`s objective was to assess factors associated with unfavorable maternal outcomes of severe preeclampsia/eclampsia, North West Ethiopian context, 2018. Methods Institutional based cross-sectional study was conducted among severe preeclamptic/Eclamptic mothers admitted in Amhara regional state referral Hospitals, Northern part of Ethiopia, 2018. All severe preeclamptic/Eclamptic mothers available during the data collection period were included as a census sampling technique. Bivariate and multivariate logistic regression model was employed. Variables with P-Value <0.05 at 95% CI level was taken as statistically significant. Data were collected with pre-tested and semi-structured questionnaire, entered into Epi-info and exported to SPSS for analysis. Results The study shows that the overall unfavorable maternal outcomes of severe preeclampsia/eclampsia were found to be 37.7% which is tragically high when compared with different previous study findings mentioned in the discussion section. Variables which were positively associated with unfavorable maternal outcomes were: Maternal educational status (AOR= 4.5, 95% CI: 1.95, 12.31), Residence (AOR= 2.1, 95% CI: 1.17, 3.72), Monthly family income (AOR= 2.7 95% CI: 1.25, 6.12), Parity (AOR= 6.7, 95% CI: 1.55, 12.6), History of abortion perceived (AOR= 3.5, 95% CI: 1.63, 7.58), Booking status (AOR= 5.8, 95% CI: 3.15, 9.72) and Time of drug given (AOR= 4.9, 95% CI: 1.86, 13.22). Conclusion and Recommendation This study revealed that the overall unfavorable maternal outcomes of severe preeclampsia and eclampsia are found to be relatively high in Amhara regional state referral hospitals. Improving booking status of pregnant women and timely providing appropriate drugs for severe pre-eclamptic/eclamptic mothers may reduce unfavorable outcomes.