Kemampuan berpikir kreatif matematis merupakan salah satu keterampilan berpikir tingkat tinggi (HOTS), yang penting dikembangkan dalam pembelajaran abad ke-21. Namun, kemampuan tersebut masih tergolong rendah dan diduga berkaitan dengan faktor psikologis siswa, salah satunya self-efficacy. Penelitian ini bertujuan untuk mengetahui hubungan antara self-efficacy dengan kemampuan berpikir kreatif matematis siswa SMK materi trigonometri. Penelitian menggunakan penedekatan kuantitatif dengan desain korelasional. Populasi penelitian adalah 288 siswa kelas X SMK Negeri Batujaya Kabupaten Karawang tahun ajaran 2025/2026, dengan sampel sebanyak 167 siswa menggunakan rumus Slovin. Instrumen penelitian meliputi tes kemampuan berpikir kreatif matematis dan angket self-efficacy yang telah teruji validitas serta reliabilitasnya serta wawancara semi terstruktur. Analisis data menggunakan uji korelasi Product Moment Pearson. Hasil penelitian menunjukkan adanya hubungan positif yang sangat kuat antara self-efficacy dan kemampuan berpikir kreatif matematis siswa, dengan nilai koefisien korelasi ? = 0,854 dan signifikansi ? < 0,001. Hal ini menunjukkan bahwa semakin tinggi self-efficacy siswa, semakin tinggi pula kemampuan berpikir kreatif matematisnya. Kata kunci: Self-efficacy, kemampuan berpikir kreatif matematis, korelasi, trigonometri Abstract: Mathematical creative thinking ability is one of the higher-order thinking skills (HOTS) that needs to be developed in 21st-century learning. However, this ability is still relatively low and is assumed to be related to students’ psychological factors, particularly self-efficacy. This study aims to determine the relationship between self-efficacy and vocational high school students’ mathematical creative thinking ability on trigonometry material. The research employed a quantitative approach with a correlational design. The population consisted of 288 tenth-grade students of SMK Negeri Batujaya, Karawang Regency, in the 2025/2026 academic year, with a sample of 167 students selected using the Slovin formula. The research instruments included a mathematical creative thinking test, a self-efficacy questionnaire that had met validity and reliability criteria, and semi-structured interviews. Data were analyzed using the Pearson Product-Moment correlation test. The results showed a very strong positive relationship between self-efficacy and students’ mathematical creative thinking ability, with a correlation coefficient of r = 0.854 and a significance level of p < 0.001. This indicates that higher self-efficacy is associated with higher mathematical creative thinking ability. Keywords: self-efficacy, mathematical creative thinking ability, correlation, trigonometry.