Penelitian ini bertujuan untuk menganalisis kemampuan literasi sains siswa kelas X SMAN 1 di Kota Tarakan. Penelitian ini merupakan penelitian deskriptif kualitatif dengan pendekatan studi kasus. Subjek dalam penelitian ini adalah 112 murid kelas X MIPA, hasil penelitian menunjukkan bahwa kemampuan literasi sains siswa kelas X SMA Negeri 1 di Kota Tarakan masih kurang dengan rata-rata nilai persentase 51% dari 112 orang siswa. Kemampuan literasi sains yang di ukur dengan 4 aspek yaitu aspek konten, kompetensi, konteks dan sikap. Berdasarkan data diketahui aspek konteks memiliki nilai persentase 48% dengan kategori kurang, aspek kompetensi memiliki nilai persentasi 43% dengan kategori kurang, aspek konten memiliki nilai persentasi 46% dengan kategori kurang, dan aspek sikap memiliki nilai persentasi 66% dengan kategori baik.

This research aimed to analyze the science literacy ability of Grade X students at SMAN 1 Tarakan. This research used a descriptive-qualitative method with a case study approach. The research subjects were 112 Grade X Science students. The results show that the science literacy ability of grade X students at SMA Negeri 1 Tarakan was still poor with the average value of 51% from 112 students. The science literacy ability was measured based on 4 aspects: content, competence, context, and attitude. Based on the research data, context aspect had the value of 48% and was classified into poor category; competence aspect had the value of 43% and was classified into poor category, content aspect had the value of 46% and classified into poor category, as well as attitude aspect had the value of 66% and classified into good category.