Ikan merupakan sumber protein yang dapat digunakan untuk fortifikasi dalam berbagai produk pangan. Untuk mempermudah proses, protein ikan dapat disediakan dalam bentuk hidrolisat bubuk atau hidrolisat protein ikan (HPI). Penelitian dilakukan untuk mengetahui jumlah terbaik HPI dalam pembuatan cookies serta pendugaan daya awetnya. Cookies dibuat dengan variasi penambahan HPI 0% (kontrol), 5%, 10% dan 15%, dan konsentrasi terbaik ditentukan dengan uji hedonik oleh 30 panelis. Cookies dengan formula terbaik selanjutnya diuji mutunya (proksimat dan mikrobiologi) dan dilakukan pendugaan umur simpan menggunakan pendekatan kadar air kritis. Cookies dengan formula terbaik adalah dengan penambahan HPI 5%, dan memiliki nilai proksimat berupa kadar protein 7,38%, kadar lemak 14,19%, kadar air 4,09%, kadar abu 1,56% dan kadar karbohidrat 72,77% serta nilai ALT 2,56x103 kol/g; dengan perkiraan umur simpan 957 hari atau 2,62 tahun. AbstractFish is a source of protein that can be used to fortify various food products. To simplify the process, fish protein can be provided in the form of hydrolyzed powder or fish protein hydrolysate (HPI). Research was conducted to determine the best amount of HPI to use in cookies production and to estimate its shelf life. Cookies were made with variations of HPI addition of 0% (control), 5%, 10% and 15%, and the best concentration was determined by a hedonic test of 30 panelists. Cookies with the best formulation were then tested for quality (proximate and microbiological) and shelf life was estimated using the critical moisture content approach. The cookies with the best formula were those with 5% HPI addition and had proximate values of protein content of 7,38%, fat content of 14,19%, moisture content of 4,09%, ash content of 1,56% and carbohydrate content of 72.77% and a microbial load (TPC) of 2,56x103 col/g. The estimated shelf life was 957 days or 2,62 years.