Background: The trend in the use of fluoroscopic-guided transcatheter aortic valve implantation (TAVI) is increasing because the procedure is less invasive than surgical procedure. However, high radiation doses have been reported with the procedure. Moreover, the amount of radiation received by patients undergoing TAVI has never before been registered in Thailand. Objectives: This study aimed to investigate the radiation dose and the effects of sex and body mass index (BMI) on the radiation dose received by patients undergoing TAVI at Chulabhorn Hospital. Materials and methods: Data were collected on the radiation dose received by patients undergoing the TAVI procedure during the first 26 months after the operation at the Cardiology Center, Chulabhorn Hospital. We recorded patient demographic data including age, sex, and BMI and the following measures of radiation dose from the procedure: the number of exposure images, air kerma-area product (PKA), cumulative air kerma at the patient entrance reference point (Ka,r), and total fluoroscopy time. Results: In total, 68 patients (35 male and 33 female) underwent TAVI, with median exposure images, PKA, Ka,r, and total fluoroscopy time of 1,067 images, 166.14 Gy/cm2, 1,171.50 mGy, and 31.90 minutes, respectively. The patient’s sex did not affect total fluoroscopy time or the radiation dose received. Patients with BMI ≥30.0 kg/m2 had the highest median values of PKA, Ka,r, and total fluoroscopy time. Moreover, patients with BMI ≥18.5-24.9 kg/m2 received higher doses of radiation than patients with BMI ≥25.0-29.9 kg/m2; the result corresponded with longer total fluoroscopy time in the lower BMI category. Conclusion: The amount of radiation that patients received during TAVI was appropriate for diagnosis and treatment. However, to ensure patient safety, operators should consider reducing the duration of radiation during the procedure. Data from this study are a starting point for the recording of radiation doses received by patients undergoing TAVI and can be used as a future dose reference.