We present a novel method to estimate the 3D pose and curvature of bendable interventional devices using a single X-ray image. A preliminary experiment was performed to demonstrate the feasibility of the proposed method. The mean estimation accuracies were 3.48mm and 0.59mm for the 3D pose and the radius of curvature of the bendable cardiac ablation catheter, respectively. This method has the potential to help clinicians to make a better intraoperative decision during the procedure, resulting in expedite surgery and reduce exposure to ionizing radiation.Clinical relevance- This novel method has the potential to improve clinician's intraoperative decision-making by providing the 3D pose and curvature information of bendable interventional devices, such as flexible catheter and endoscope.