A method of producing sizing agent-applied carbon fiber bundles includes a sizing agent application process of immersing a plurality of carbon fiber bundles running side by side in a sizing agent bath, followed by a dry process performed to obtain sizing agent-applied carbon fiber bundles and, to address issues of wrapping of a carbon fiber bundle caused by sticking of a sizing agent solution to a guide roller, the first guide roller for the carbon fiber bundles after being immersed in the sizing agent bath and coming out of a liquid surface of the sizing agent bath is set to have a surface adhesive force of 0.2 N/cm.sup.2 or less.