The development of novel robotic devices specifically designed for open microsurgery leads to increasing applications in reconstructive procedures. While initial studies revealed improved precision and surgical ergonomics upon robotic assistance, surgical time was consistently observed to be increased. This study compares two robotic suturing techniques using the Symani Surgical System and RoboticScope in a preclinical setting, to further leverage the benefits of novel robotic devices in microsurgery. Six experienced microsurgeons performed three microvascular anastomoses with a “steady-thread” suturing technique and a “switch-thread” technique on 1.0-mm-diameter artificial silicone vessels. Time for anastomosis and participant’s satisfaction with the techniques and robotic setup were recorded. Anastomosis quality and microsurgical skills were assessed using the Anastomosis Lapse Index and Structured Assessment of Microsurgery Skills. Lastly, technical error messages and thread ruptures were quantified. Knot tying was significantly faster and evaluated significantly better by participants using the steady-thread technique (4.11 ± 0.85 vs. 6.40 ± 1.83 min per anastomosis). Moreover, microsurgical skills were rated significantly better using this technique, while both techniques consistently led to high levels of anastomosis quality (2.61 ± 1.21 vs. 3.0 ± 1.29 errors per anastomosis). In contrast, the switch-thread technique was associated with more technical error messages in total (14 vs. 12) and twice as many unintended thread ruptures per anastomosis (1.0 ± 0.88 vs. 0.5 ± 0.69). This study provides evidence for the enhanced performance of a steady-thread suturing technique, which is suggested to be applied upon robot-assisted microsurgical procedures for optimized efficiency.