Data on the relationship between arterial pulsatile hemodynamics and aortic root geometry, using invasive hemodynamic measurement, has been scarce. Thus, this study aimed to assess the relationship between invasively measured aortic pulse pressure (aPP) and the diameter of ascending aorta (AoD). We analyzed 665 subjects (64.3 ± 11.0 years; 34.6% female) who underwent elective invasive coronary angiography (ICA) for the evaluation of coronary artery disease. Transthoracic echocardiography was performed on the same day, and AoD was measured at the level of 1 cm above the sinotubular junction at the end-diastole. Body surface area (BSA)-adjusted AoD (AoD/BSA) was used for the analysis. A pig-tail catheter was used to measure aortic pressures at a level approximately 3 cm above the aortic valve just before ICA. aPP was calculated as the difference between systolic and diastolic pressures of the aorta. In multiple linear regression analyses, aPP (β = 0.259; P < 0.001) was found to be significantly correlated with AoD/BSA even after controlling for potential confounders. This correlation power was stronger than aortic systolic pressure (β = 0.189; P < 0.001) and brachial pulse pressure (β = 0.091; P = 0.018) at the same multivariable analyses. In conclusion, our study demonstrated a significant association between invasively measured aPP and AoD/BSA, providing stronger evidence for the link between central aortic pulsatile hemodynamics and aortic root geometry.