Electrochemical measurements and surface analysis are performed to comparatively study flow-accelerated corrosion (FAC) and erosion-corrosion (E-C) behavior at a 90° carbon steel bend. The corrosion rates are higher under FAC conditions than those under E-C conditions. For FAC, the corrosion is more serious at the inside wall. However, corrosion is exacerbated at the outside wall under E-C conditions. No erosion scratches are observed under FAC conditions and at the inside wall under E-C conditions, while remarkable erosion scratches appear at the outside wall under E-C conditions. The dominant hydrodynamics affecting FAC and E-C are remarkably different.