This study explored affective factors in learning English as a foreign language in a 3D game-like virtual world, Quest Atlantis (QA). Through the use of communication tools (e.g., chat, bulletin board, telegrams, and email), 3D avatars, and 2D webpage navigation tools in virtual space, nonnative English speakers (NNES) co-solved online content-related problem quests with native English speakers (NES). Students in the QA group rated themselves higher than the non-QA group in self-efficacy toward advanced use of English, attitude toward English, and self-efficacy toward e-communication. These findings suggest that virtual worlds may provide a space for English language learners (ELLs) in the United States and other countries to increase confidence and comfort and to overcome cultural barriers for learning English. (Contains 9 tables and 2 figures.)