This article considers the implications of the thinking ability in the oral communication of second language(L2) learners.Even though the critical thinking movement is expanding throughout academia,research in second language acquisition(SLA) has been noticeably lacking in establishing the relationship between L2 oral communication and thinking.This study investigated oral problem solving in EFL(English as a Foreign Language) learners in the People’s Republic of China.The main question asks if advanced EFL learners’ problem solving efficacy will be reduced when having to solve nonverbal puzzles while speaking in English in comparison solving these puzzds while to speaking in Chinese or remaining silent.Results found that participants in silent and Chinese speaking conditions had an insignificant difference in accuracy.However,speaking in English had significant deleterious effects,reducing accuracy by 24.5% in comparison to those participants in the silent condition.A paradigm shift for oral communication in SLA is offered for pedagogy and research.