Penelitian ini bertujuan untuk melihat keefektifan pembelajaran kontekstual terhadap kesulitan belajar dan kemampuan penalaran matematis siswa. Populasi pada penelitian ini adalah siswa kelas VIII semester I SMP Negeri 1 Dukuhturi Tahun Pelajaran 2018/2019. Pengambilan sampel dengan cluster random sampling. Sampel yang diambil sebanyak 3 kelas, yaitu kelas eksperimen, kelas kontrol dan kelas uji coba. Pengumpulan data menggunakan angket dan tes. Teknik analisis data yang digunakan uji proporsi, uji t satu pihak kanan, uji manova, dan uji -Hotelling. Hasil penelitian menyatakan bahwa pembelajaran matematika yang diajar menggunakan pembelajaran kontekstual dapat melampaui target, pembelajaran kontekstual lebih baik daripada pembelajaran konvensional terhadap kesulitan belajar, dan terhadap kemampuan penalaran matematis siswa, ada perbedaan yang signifikan kesulitan belajar dan kemampuan penalaran matematis antara siswa yang diajar menggunakan pembelajaran kontekstual dengan siswa yang diajar menggunakan pembelajaran konvensional, pembelajaran kontekstual lebih baik daripada pembelajaran konvensional terhadap kesulitan belajar dan kemampuan penalaran matematis siswa. Kata kunci: keefektifan, pembelajaran kontekstual, kesulitan belajar matematika, kemampuan penalaran matematis This study aims to look at the effectiveness of contextual learning on learning difficulties and students' mathematical reasoning abilities. The population in this study were students of class VIII in the first semester of SMP Negeri 1 Dukuhturi Academic Year 2018/2019. Sampling by cluster random sampling. The samples taken were 3 classes, namely the experimental class, the control class and the trial class. Data collection uses questionnaires and tests. The data analysis technique used is the proportion test, the right one t test, the manova test, and the 2 ^ 2-Hotelling test. The results of the study state that mathematics learning taught using contextual learning can exceed the target, contextual learning is better than conventional learning on learning difficulties, and on students' mathematical reasoning abilities, there are significant differences in learning difficulties and mathematical reasoning abilities between students taught using contextual learning with students taught using conventional learning, contextual learning is better than conventional learning on learning difficulties and students' mathematical reasoning abilities. Keywords : effectiveness, contextual learning, difficulty learning mathematics, mathematical reasoning abilities.