PURPOSE: Cancer care in low-income countries poses formidable challenges. Care may be facilitated by resource-adapted guidelines, such as the National Comprehensive Cancer Network (NCCN) harmonized guidelines for sub-Saharan Africa (NCCN-HG). Understanding physicians' attitudes and knowledge toward guidelines, as well as patient- and resource-related barriers, is essential for promoting their effective implementation. METHODS: We conducted an online survey among oncologists, hematologists, internists, residents/fellows, and generalists treating hematologic malignancies in Ethiopia. We assessed attitudes toward the use of guidelines, institutional capacity, and barriers/determinants to effective care. RESULTS: Among the 47 physicians completing the survey (representing 64% of Ethiopian professionals treating hematologic malignancies), the majority (85%) reported using guidelines; however, only 22.7% (n = 10) used the NCCN-HG. While overall attitudes toward guidelines were favorable, 57.8% of physicians familiar with the NCCN-HG were either undecided or believed that it lowers the standard of care. Perceived lack of institutional regulation was negatively associated with guideline use (B = -3.23; P = .004). Lack of diagnostic facilities including immunohistochemistry and flow cytometry, supportive care, and poor utilization of guidelines were reported to be determinants of poor patient outcome. Regarding patient factors, 57.4% respondents identified treatment abandonment as an important contributor to poor outcome. Availability of chemotherapy/radiotherapy (89.4%), financial status (85.1%), distance from the hospital (74.5%), and harvest season (65%) had major influences on treatment decisions. Over 80% reported that targeted therapies were unavailable or rarely available. CONCLUSION: Awareness and usage of the NCCN-HG are limited among Ethiopian physicians. Lack of facilities, therapies, and regulation, in addition to patient-related factors, was identified as barriers to guideline adherence and determinants of poor outcome.