This study investigated children's motivation for learning English as a foreign language (EFL) and intrinsic motivation for learning in general. The participants were 268 third-sixth graders in a public school in Japan. Data were collected using two questionnaires, one measuring motivation for learning EFL and the other investigating intrinsic motivation for studying in general. Multivariate Analysis of Variance (MANOVA) indicated that intrinsic motivation for studying in general as well as motivation for learning EFL of the participating students generally decline from third through sixth grades. The results of a multiple-regression analysis indicate that curiosity is a predictor of intrinsic motivation for learning EFL, interest in foreign countries, and instrumental motivation; enjoyment is a positive predictor of intrinsic motivation for learning EFL and interest in foreign countries; endogenous attribution is a negative predictor of instrumental motivation; and internal causality is a positive predictor of instrumental motivation. It can be suggested that a developmental decline in intrinsic motivation for studying in general might influence English lessons.