This study was conducted to investigate elementary school teachers' attitudes and motivation toward web-based professional development. The relationship between teachers' attitudes and motivation was explored using the AWPD (Attitudes toward Web-based Professional Development) and MWPD (Motivation toward Web-based Professional Development) surveys, respectively. The AWPD consisted of five scales, including "Perceived usefulness", "Perceived ease of use", "Affection", "Anxiety", and "Behavior". The MWPD also consisted of five scales, including "personal interest", "social stimulation", "external expectation", "practical enhancement", and "social contact". Data gathered from 322 elementary school teachers were examined through structural equation modeling. The results indicate that, in general, the teachers' attitudes and their motivation toward web-based professional development were significantly positively correlated with each other. It was also found that teachers with higher motivation have more positive attitudes toward web-based professional development. (Contains 4 tables.)