The purpose of this study is to describe the effectiveness of learning mathematics using the Think-Talk-Write (TTW) strategy and conventional learning approaches in terms of critical thinking and mathematical communication, comparing the effectiveness of Think-Talk-Write (TTW) strategy and conventional learning approaches in terms of thinking. critical and mathematical communication. The research methods is a quasi-experimental, the population in this study was students of class X MA Bahrul Ulum Jombang, totaling three classes. Based on the sampling, it was obtained that class X-IIS-1 as the experimental class and class X-IIS-II as the control class. The data was analyzed using the one-sample t-test, MANOVA test with T2 Hotteling and t test with Bonferroni Criteria. The results of research showed that at the 95% level of significansy,(1) The application of the Think-Talk-Write (TTW) learning strategy is effective, while the application of conventional learning is not effective in terms of critical thinking skills and mathematical communication.(2) The application of the Think-Talk-Write (TTW) learning strategy is more effective than the application of conventional learning in terms of critical thinking skills and mathematical communication.