For Bennett fractures with tiny avulsion fragments, healing may be jeopardized owing to limited fracture contact surface if displacement of reduced fracture junctions occurs. This study aimed to assess the efficacy of treating Bennett fractures with tiny avulsion fragments using percutaneous small-diameter K-wires for tiny fragment fixation and thumb carpometacarpal (CMC) joint transfixation. From 2011 to 2019, we retrospectively enrolled patients with Gedda type 3 Bennett fractures who underwent operation with K-wire percutaneous pinning for the tiny fragment and CMC joint. We enrolled a total of 13 patients (13 fractures) with a mean age of 26.9 years (range, 18-42 years) at operation and a mean follow-up time of 17.9 months (range, 12-34 months). At the final follow-up, the shortened Disabilities of the Arm, Shoulder and Hand Questionnaire mean score was 4.7, and the visual analog scale score for pain during activity was 0.7. Mean grip strength was 34.7 kg (97.7% of the value on the unaffected side). Mean pinch strength was 5.4 kg (90.5% of the value on the unaffected side). Mean first web opening angle was 66.2° (96.6% of the value on the unaffected side). There were no changes in gap and step-off during the healing process and no osteoarthritic changes in the thumb CMC joint at the final follow-up. For Bennett fractures with tiny avulsion fragment, percutaneous treatment with small-diameter K-wires for fragment fixation and thumb CMC joint transfixation provides a viable alternative with fracture healing and good functional outcomes. [Orthopedics. 2023;46(2):103-107.].