Background Currently, breast conservation therapy is commonly performed for the treatment of early breast cancer. Depending on the volume excised, patients may require volume replacement, even in cases of partial mastectomy. The use of the latissimus dorsi muscle is the standard method, but this procedure leaves an unfavorable scar on the donor site. We used an endoscope for latissimus dorsi harvesting to minimize the incision, thus reducing postoperative scars. Methods Ten patients who underwent partial mastectomy and immediate partial breast reconstruction with endoscopic latissimus dorsi muscle flap harvest were reviewed retrospectively. The total operation time, hospital stay, and complications were reviewed. Postoperative scarring, overall shape of the reconstructed breast, and donor site deformity were assessed using a 10-point scale. Results In the mean follow-up of 11 weeks, no tumor recurrence was reported. The mean operation time was 294.5 (±38.2) minutes. The postoperative hospital stay was 11.4 days. Donor site seroma was reported in four cases and managed by office aspiration and compressive dressing. Postoperative scarring, donor site deformity, and the overall shape of the neobreast were acceptable, scoring above 7. Conclusions Replacement of 20% to 40% of breast volume in the upper and the lower outer quadrants with a latissimus dorsi muscle flap by using endoscopic harvesting is a good alternative reconstruction technique after partial mastectomy. Short incision benefits from a very acceptable postoperative scar, less pain, and early upper extremity movement.