This study aimed at investigating the effectiveness of "Philosophy for Children (P4C)" approach on the critical thinking and English-speaking skills of twenty-three 7 th grade gifted students learning English as a foreign language at a Science and Art Center (SAC) in the city of Denizli, Türkiye. In the study a mixed methods research design was adopted with the participation of randomly assigned experimental and control groups. While quantitative data were collected through the Cornell Critical Thinking Test (CCTT) X level and the Cambridge English Speaking Test (A2 level for Schools), qualitative data were collected through reflective diaries written by the experimental group participants and evaluation forms. While the control group followed the usual SAC English speaking lessons, English speaking lessons for the experimental group were based on the P4C approach. According to the quantitative data findings, there was an increase in the scores of both groups in terms of speaking skills in English, however this difference was not statistically significant. In terms of critical-thinking skills, there was a slight decrease between the pre-test and post-test scores of the control group and an increase in the scores of the experimental group and this difference was statistically significant. In addition, the qualitative data revealed that the experimental group participants generally provided positive feedback on P4C practices and speaking lessons based on the P4C approach created positive effects on their critical thinking and speaking skills in English, while such an application did not create a significant effect on their speaking skills in English.