Abstrak Tujuan penelitian ini adalah mendiskripsikan kurva moisture ratio dan melakukan pendugaan lama pengeringan dendeng ikan manyung (Arius thalasisinus) dengan Pengering Energi Surya YSD-UNIB12. Percobaan dilakukan dengan mempersiapkan sampel sesuai dengan cara pembuatan dendeng ikan dan selanjutnya tiga perlakuan ditetapkan yaitu ketebalan dendeng (0,5 cm dan 1 cm), lama perendaman dalam larutan bumbu (1 jam, 3 jam dan 5 jam), dan posisi sampel pada rak yaitu rak1 (bawah), rak2 (tengah) dan rak3 (atas), masing-masing dilakukan dengan tiga ulangan. Pengamatan dilakukan terhadap suhu dan kelembaban relatif ruang pengering dan udara luar, dan penurunan berat sampel sepanjang proses pengeringan dari pukul 09.00-16.00 WIB sampai pengeringan selesai dengan kadar air akhir ikan 12%. Hasil percobaan menunjukkan bahwa pengering mampu menaikkan suhu udara 15,2 oC lebih tinggi dari udara luar dan menurunkan kelembaban relatif 31% lebih rendah dari udara luar. Model kurva hubungan antara moisture ratio dan kadar air dengan waktu pengeringan adalah kuadratik. Lama pengeringan hanya dipengaruhi oleh tebal dendeng dan posisi di rak. Rata-rata waktu penyelesaian pengeringan berkisar antara 11,9 jam sampai 30,3 jam. Kata kunci: kadar air, lama waktu pengeringan, moisture ratio, pendugaan Abstract The objectives of this study were to describe the curves of moisture ratio and moisture content and to predict drying times of the jerked flesh of Manyung fish (Arius thalassinus) dried by utilizing YSD-UNIB12 solar. The experiments were set up by employing three treatments, i.e., thickness of jerked flesh (0.5 cm and 1 cm), flesh submerging time in spices solution (1, 3 and 5 hours), and rack’s positions that were rack1 (lower), rack2 (middle) and rack3 (upper) with three replications each. The observation was carried out at 9 AM to 4 AM for drying room temperature and relative humidity, ambient temperature and relative humidity, and weight of samples along drying process until the fish moisture content of 12%. The result of experiments showed that the dryer generated the drying chamber temperature 15.2oC higher than the ambient temperature, and the drying chamber relative humidity 31% lower than the ambient relative humidity. Both models of curves of moisture ratio and moisture content versus drying time were quadratic (polynomial second order). Only the position of the rack and the thickness of jerked fish affected drying time. The drying time to produce dry jerked fish varied from 11.9 hours to 30.3 hours Keywords: drying time, moisture content, moisture ratio, prediction