Penelitian ini bertujuan untuk mengetahui prosedur penilaian autentik dalam pembelaran biologi, kesesuaian dalam penerapan penilaian autentik guru biologi terhadap standar proses penilaian kurikulum 2013, dan kendala yang dialami guru biologi di SMA Negeri 1 Tarakan dalam pelaksanaan penilaian autentik sesuai dengan kurikulum 2013. Metode penelitian menggunakan pendekatan deskriptif kualitatif. Subjek penelitian 3 guru mata pelajaran biologi, wakil kurikulum dan 24 peserta didik dengan penentuan sampel menggunakan purposive sampling. Data diperoleh berdasarkan hasil observasi, dokumentasi, angket dan wawancara. Hasil penelitian menunjukkan bahwa prosedur penilaian autentik pada pembelajaran biologi sudah berjalan dengan baik. Pada tahap perencanaan diperoleh hasil sebesar 86,6%, pada tahap pelaksanaan diperoleh hasil sebesar 85,1%, dan pada tahap pelaporan diperoleh hasil 83,3%. Kesesuaian pelaksanaan penilaian autentik pada pembelajaran biologi dalam aspek sikap, aspek pengetahuan, dan aspek keterampilan sudah sesuai dengan Permendikbud No. 23 Tahun 2016 tentang standar penilaian pendidikan, dan kendala guru dalam pelaksanaan penilaian autentik pada pembelajaran biologi adalah kendala waktu yang terbatas karena pandemik covid, biaya yang lebih banyak, banyaknya komponen/kriteria dalam penilaian autentik, kurangnya motivasi siswa dalam mengikuti pembelajaran yang inovatif dengan penilaian autentik serta prasarana yang tidak berfungsi dengan baik.

The purpose of this study was to identify the authentic assessment process in biology learning, the suitability of applying authentic assessment of biology teachers to the standard 2013 curriculum assessment process, and the challenges faced by biology teachers at SMA Negeri 1 Tarakan in implementing authentic assessment in line with the 2013 curriculum. Three biology professors, curriculum representatives, and 24 students were the research subjects. The sample was chosen via purposive sampling. The data were obtained based on the results of observations, documentation, questionnaires, and interviews. The results showed that biology learning’s authentic assessment process was operating successfully. Results of the planning stage were 86.6 percent, those for implementation stage were 85.1 percent, and those for the reporting stage were 83.3 percent. In terms of attitudes, knowledge aspects, and skill aspects, the implementation of the authentic assessment of biology learning complied with Permendikbud No. 23 of 2016 about educational assessment standards. Limited time due to the covid pandemic, higher costs, numerous components and criteria in authentic assessment, a lack of student motivation to engage in innovative learning with authentic assessments, and inadequate infrastructure were some of the challenges faced by teachers when implementing authentic assessments in biology learning.