Catheter‐based renal denervation (RDN) is currently being developed as a new complementary treatment option for hypertension. RDN has not yet received approval in Japan and so the number of possible candidates for RDN in Japan also remains unknown. A total of 10 756 hypertensive patients who regularly visit medical institutions and reported their latest home blood pressure (BP) values were identified from registrants at an online research company. They filled out a survey regarding their prescribed antihypertensives and latest BP values in March 2020 in Japan. The mean age of the patients was 61.3 years old (83.5% male). According to JSH 2019, the prevalence of resistant hypertension (RHT) was estimated to be 1.4% (0.52% having an office BP of 140/90 mm Hg or more while taking three antihypertensives, including diuretics; 0.84% taking four or more antihypertensives regardless of BP level). Assuming the indication for RDN was RHT with morning home systolic BP (HSBP) ≥ 135 mm Hg and office systolic BP (OSBP) ≥ 140 mm Hg, the number of candidates for RDN was estimated to be approximately 340 000 and 372 000, respectively. When hypertensive patients prescribed three or more, two, one, and no antihypertensives were included, the estimated number based on uncontrolled HSBP and OSBP cumulatively increased 2.6, 14.2, 40.6, and 58.0‐fold; 1.8, 8.6, 25.3, and 36.4‐fold, respectively. These findings revealed that a substantial number of hypertensive patients are unable to adequately control their BP level with existing treatments, and new complemental therapies, such as RDN, would alleviate the burden of hypertension in this population.