We previously reported safety and usefulness of transradial iliac artery stenting using 6 Fr guiding sheath. However, radial artery occlusion was a major limitation of this procedure. We analyzed the safety and utility of slender transradial iliac artery stenting using a 4.5 Fr guiding sheath to prevent radial artery occlusion. We performed transradial iliac artery stenting in left radial artery, using a 4.5 Fr sheath incorporating a shaft length of 110 cm, for 34 lesions in 29 patients. Transradial intervention was attempted at the discretion of the operator. Clinical data were analyzed retrospectively. Cases with scheduled multiple sheath insertions for a bidirectional approach were excluded. Twenty-three (79.3%) patients were male. Diabetes mellitus, hypertension, dyslipidemia, and smoking habit were present in 11 (37.9%), 27 (93.1%), 19 (65.5%), and 24 (82.8%) patients, respectively. Nine lesions (26.5%) were diagnosed as chronic total occlusion. All lesions were successfully treated using a total of 40 stents incorporating a 4.5 Fr radial access system. Ankle-brachial index (ABI) significantly improved from 0.68 ± 0.15 to 0.99 ± 0.17 (p < 0.0001) after the procedure. No patients had procedural or access site-related complications such as hematoma, major bleeding, blood transfusion, stroke, cholesterol embolism, aortic dissection, or arterial perforation. Radial artery occlusion was absent in all cases. ABI value was well maintained at 0.98 ± 0.13 at 1 year, and no target lesion revascularizations were reported. Slender transradial iliac artery stenting using a 4.5 Fr guiding sheath is safe, feasible, and less invasive, and shows no incidence of radial artery occlusion, in carefully selected patient populations.