Purpose: Computer-guided surgery has been increased in recent years. Nonetheless, few data are available on the validation of this technique for immediate implant placement. The purpose of this in vitro study was to evaluate the accuracy of computer-guided surgery in immediate implant placement. Materials and Methods: Cone-beam computed tomography scans (CBCTs) and virtual models were obtained of eight fresh pigs hemi-mandibles to perform the digital planning of implants placement. Fifteen implants were simulated, and surgical guides were designed to transfer the digital planning to the surgical procedure. Postsurgical CBCTs were performed to compare the position of the planned implants versus the real implant position. Paired t-test and the intra-class correlation coefficient (ICC) were used to assess the mean differences and correlations in each outcome variable evaluated twice by one experienced researcher. Furthermore, variations were compared with the results reported in the scientific literature using a one-sample t-test P < 0.05. Results: The measurements of the outcome variables (implants position at the neck and apex level and the angular deviation) showed significant reproducibility (mean difference-0.01 mm, 0.07 mm, and 0.30°, respectively, P > 0.05). The ICC values ranged from 0.888 to 0.949. Furthermore, the mean deviation was 1.43 mm at the implant neck, 2.19 mm at the apex, and 6.81° for the angular deviation. Similarly, significant differences (P < 0.05) were found at the neck and angular deviation when comparing the results with values reported in the literature. Conclusions: Although some variations were observed, they did not have a clinically significant impact. Therefore, computer-guided surgery could be satisfactorily used in immediate implants placement.