Statement of problem: The accurately placed dental implant using surgical guides in the exact pre-designed position is multifactorial goal that subjected to different factors including the method of guides manufacturing. Purpose: To evaluate the accuracy of CAD/CAM milled and 3D printed surgical guides Materials and methods. Fifteen identical mandibular Kennedy Class III modifications 1 partially edentulous stone models with missed first molar in both side were selected for the study. Preoperative CBCT of the models were done. Implants were placed virtually at the position of first molars was done. Surgical guides were designed, saved in STL format. Each model was distributed into two main groups with right side and left side according to: Group I: Surgical guides were 3D printed. Group II: Surgical guides were CAD/CAM milled. Implants were installed in the models using surgical guides. Postoperative CBCT scans of the models were done. Preoperative and postoperative scans were superimposed and compared concerning actual implant and virtually planned positions. Measuring three deviation parameters was done between each planned and actual implant positions: apical deviation (mm), Coronal deviation (mm) and angular deviation (°). The distance between the actual and planned points in the x, y, and z-axis were measured. Data were collected and analyzed. Independent t-test was used to compare between the two groups at the level of significance (p value ≤0.05).