OBJECTIVES: The robot-assisted cortical bone trajectory (CBT) screw placement is safer than the traditional fluoroscopy-assisted approach. This is the first technical note reporting a novel technique of robot-assisted CBT screws placement with a subfascial transmuscular approach. TECHNICAL NOTE: After a lumbar interbody cage position, the second step consists in the robot-assisted placement of CBT screws in a prone position. A median skin incision is performed, ensuring an incision as small as possible. CBT screw direction and trajectory are planned on the sterile robot touchscreen display. A navigated drill is used to breach the cortical surface of the entry point. Then, a navigated drill bit is used to complete the exposure of the screw trajectory. The screw is placed with the support of the robotic arm. In the single-position the surgical field must be prepared since the first surgical step. All the navigation references are placed on the same iliac crest. The following steps resemble the ones described for the double-position. CONCLUSION: This is the first reported technical note about robot-assisted transmuscular CBT screw placement for posterior fixation in LLIF. The surgical technique proposed aims to combine the advantages of CBT screws and the use of innovative robot-assisted technology.