The present study intends to provide empirical evidence on the effect of Philosophy for Children (P4C) integrated with English picture storybook instruction on adolescent learners of English as a foreign language. Previous studies have documented the instructional benefits of P4C in various fields; very little evidence, however, can be found in ESL (English as a second language) or EFL (English as a foreign language) contexts. The present study was therefore carried out to explore the beneficial effects of P4C applied in EFL instruction with picture storybooks as instructional materials. A total of 62 students participated in the study, divided into one P4C group and one non-P4C group. Participants in the P4C group underwent 10 weeks of English storybook instruction with P4C in a school club, and the effects of instruction were measured by questionnaires and reading comprehension tests. Results of the study showed that students in the P4C group experienced a slightly higher level of English learning anxiety, retained higher English learning motivation after the instruction, and improved their English reading comprehension. Finally, pedagogical implications are presented.