Introduction: Type 2 Diabetes Mellitus has characteristic dyslipidemia. Low-density lipoprotein cholesterol (LDLC) measurement plays a role in cardiovascular risk assessment and management. Friedewald equation (FE) has several limitations. This study aims to evaluate the effectiveness of Martin equation (ME) in Egyptian patients, especially those with type 2 diabetes. Methods: A cross-sectional study was conducted on 454 diabetic and non-diabetic patients who were referred to the internal medicine outpatient clinic. Lipid profile was assessed by Cobas 8000 Modular Analyzer. Results: The LDL-C was estimated by both FE and ME. In diabetic patients, LDL-C estimated by FE was underestimated with a bias of −3.9 ± 5.3 mg/dL (p=.04). But LDL-C estimated by ME was not significantly different compared to directly measured LDL-C. FE underestimate LDL-C with a bias of −4.6 ± 6.4 mg/dL (p=.042) in uncontrolled diabetic patients. A non-significant difference in both uncontrolled patients and controlled ones was detected by ME. FE had lower sensitivity and specificity (80% and 88.9 respectively) compared to the ME (95.9% sensitivity, and 95.6% specificity). ME was not influenced by triglyceride levels (p=.34). Conclusion: The ME improves concordance of calculated LDL-C with a direct LDL-C assay in Egyptian diabetic patients.