We prospectively analyzed the functional and clinical results of patients who underwent a single end-to-end suture and an augmented tendon repair with plantaris tendon at middle-term follow-up. From January 2003 to May 2005, 30 consecutive patients were operated on for the treatment of acute Achilles' tendon rupture by means of 2 different methods. No cases required adjunctive procedures to allow for acceptable end-to-end apposition. All ruptures were acute and repairable. The patients were divided into 2 groups. In group 1, augmentation with plantaris tendon was performed in addition to the Krakow end-to-end suturing technique in 16 patients, and in group 2, only the Krakow end-to-end suturing technique was used in 14 patients. The average age of the patients was 40.6 years. Patients in the study groups were followed up at a mean of 17.8 months after surgery. At the end of the follow-up, functional and subjective outcome scores were evaluated. The American Orthopaedic Foot and Ankle Society hindfoot clinical outcome scores were 96.7 in group 1 and 98.8 in group 2. Although there was a numerical increase in group 2, no significant difference was determined between the 2 study groups statistically. The surgical outcome concerning local tenderness, skin adhesion scar, and tendon thickness was better in group 2 than in group 1 without a statistical significance. Although functional outcomes of both treatment groups were the same, the end-to-end suturing technique provided a safer and more reliable treatment with a low risk of complications in the treatment of acute Achilles' tendon ruptures compared with the plantaris tendon augmentation technique.