Penelitian ini bertujuan untuk mengeksplorasi Pengembangan Keprofesian Berkelanjutan (PKB) dalam kaitannya dengan kompetensi dan praktik pembelajaran yang dilakukan guru matematika SMA di Kabupaten Kulon Progo. Penelitian ini merupakan penelitian deskriptif menggunakan metode campuran, dengan desain penelitian convergent parallel design. Subjek dalam penelitian ini adalah seluruh guru SMA peserta Ujian Kompetensi Guru (UKG) matematika tahun 2015 di Kabupaten Kulon Progo yang berjumlah 33 guru. Teknik pengumpulan data yang digunakan adalah tes, angket, observasi, dokumentasi, dan wawancara. Teknik analisis data yang digunakan untuk data kuantitatif yaitu deskriptif dan Partial Least Squares Structural Equation Modeling (PLS-SEM). Analisis data kualitatif dianalisis melalui pengkategorian, reduksi data, penyajian data, dan penarikan kesimpulan. Hasil penelitian menunjukkan bahwa: (1) terdapat pengaruh yang signifikan PKB terhadap kompetensi guru matematika SMA di Kabupaten Kulon Progo dengan nilai prediksi sebesar 0,360 (t = 2,51); dan (2) terdapat pengaruh yang signifikan PKB terhadap praktik pembelajaran guru matematika SMA di Kabupaten Kulon Progo dengan nilai prediksi sebesar 0,402 (t = 2,25). Continuing Professional Development (CPD) in relation to the competence and learning practices of high school mathematics teachersAbstractThis study aimed to explore Continuing Professional Development (CPD) in relation to the competence and teaching practice conducted by senior high school mathematics teachers in Kulon Progo Regency. This study was descriptive research using a mixed-method with convergent parallel design. The research subject was all senior high school mathematics teachers in Kulon Progo Regency who participated in the Teacher Competency Test (or UKG) in 2015, and the subject applied was 33 teachers. The data collection was conducted through a test, questionnaire, documentation, observation, and interview. The data analysis used was descriptive and Partial Least Squares Structural Equation Modeling (PLS-SEM). Qualitative data was analyzed through data categorization, data reduction, data presentation, and conclusion drawing. The results of the study showed that: (1) there was a significant influence CPD toward competence of senior high school mathematics teachers in Kulon Progo Regency with prediction value 0.360 (t = 2.51); and (2) there was a significant influence CPD toward teaching practice of senior high school mathematics teachers in Kulon Progo Regency with prediction value 0.402 (t = 2.25).