Objective: This study aimed to identify determinant factors of stunting and wasting in street children ages 5 to 18 y in Northwest Ethiopia. Materials and methods: A community-based cross-sectional study design was employed. An interviewer-administered, structured, and pretested questionnaire was used to collect the data. A convenience sampling technique was used to recruit participants. Stunting and wasting were defined as having a height-for-age and weight-for-height Z score of less than -2 SDs, respectively. Both bivariable and multivariable logistic regression analyses were fitted to identify factors associated with stunting and wasting. A 95% confidence interval (CI) and P < 0.05 were used to declare statistical significance. Results: The overall prevalence of stunting and wasting was 46.4% (95% CI: 41.6-51.5%) and 15.3 % (95% CI: 11.7-19.0%), respectively. Age (adjusted odds ratio [AOR] = 0.18, 95% CI: 0.08, 0.47), substance use (AOR = 2.07, 95% CI: 1.33, 3.21), and loss of appetite (AOR = 2.00, 95% CI: 1.31, 3.04) were independently associated with stunting. Whereas age (AOR = 0.49, 95% CI: 0.27, 0.89), illness (AOR = 2.38, 95% CI: 1.27, 4.48), and open defecation (AOR = 2.27, 95% CI: 1.14, 4.51) were factors associated with wasting. Conclusion: Stunting and wasting were found to be critical problems in street children. Age, loss of appetite, and substance use were significantly associated with stunting, whereas child age, illness, and open defecation practice were significantly associated with wasting. Thus, tailored nutritional interventions are urgently required in this population to improve their nutritional status. (c) 2021 The Author(s). Published by Elsevier Inc. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/)