Statement of problem: Titanium is the most biocompatible metal used for dental casting; however, there is concern about its marginal accuracy in compare to the nickel-chrumium alloy. Purpose: The purpose of this study was to to evaluate and compare the marginal accuracy and internal fit of milled titanium and cast nickel-chromium single unit restorations. Material and methods: Milled titanium copings (n=20) and cast Ni-Cr copings (n=20) were fabricated with different axial taper (6,10 degree) and finish line (shoulder, chamfer) The copings were subjected to the firing cycle of the porcelain. Marginal and internal gap distance measurements were done using the internal replica technique.by Using a stereomicroscope a total number of 46 readings was giving for each replica. Obtained data were recorded, averaged and statistically analyzed. Results: ANOVA showed that The convergence angle and The finish line type has no influance on the marginal accuracy of milled titanium copings (P ≤ 0.05). Chamfer F.L displayed the least magnitude of marginal discrepancy with both techniques. Conclusions: Cast Ni-Cr alloy copings showed less marginal gap measurements than milled Titanium copings with different preparation parameters. The obtained marginal gap measurements of all copings are within the clinical acceptable range.