Yellow tail fish (Caesio cuning) surimi contains high protein levels but low fat levels. Freeze storage as an alternative toward surimi in order to does not occur putrefaction that is been caused by microorganism. The purpose of this research is to study the difference fat content in surimi of yellow tail fish before and after frozen storage. This study used purposive sampling experiments with methods and techniques of analysis test average of two populations (Independent t-Test) with two treatment products surimi freezing storage before and after each with five replications. Quantitative data were analyzed using SPSS version 17 software. The results of the research there is a difference in fat levels decrease significantly that is average in frozen surimi prior to 30.274% while after frozen storage 20.961%. It can be concluded that the storage of frozen surimi experienced a significant decrease in fat levels, so there is a difference between before and after frozen storage, where fat loss of 9.31%. Result is a high decrease of fat in freezer, because fat loss more than 5%. Keywords: freeze storage, fat content, surimi yellow tail fish ABSTRAK Surimi ikan ekor kuning (Caesio cuning) mengandung kadar protein tinggi tetapi kadar lemaknya rendah. Penyimpanan beku sebagai salah satu alternatif agar surimi tidak membusuk sebab aktifnya mikroorganisme. Tujuan dari penelitian ini adalah untuk mempelajari perbedaan lemak surimi ikan ekor kuning (Caesio cuing) sebelum dan sesudah penyimpanan beku. Penelitian ini menggunakan metode eksperimen dengan purposive sampling dan teknik analisis uji rerata dua populasi dengan dua perlakuan produk surimi sebelum dan sesudah penyimpanan beku masing-masing dengan lima kali ulangan. Data kuantitatif dianalisis menggunakan softwere SPSS versi 17. Hasil penelitian terdapat perbedaan penurunan kadar lemak yang signifikan yaitu rerata pada surimi sebelum penyimpanan beku 30,2741% sedangkan sesudah penyimpanan beku 20,9608%. Surimi penyimpanan beku mengalami penurunan kadar lemak yang signifikan, sehingga terdapat perbedaan antara produk surimi sebelum dan sesudah penyimpanan beku, penurunan lemak sebesar 9,31% dan hasil tersebut merupakan penurunan lemak yang tinggi dalam penyimpanan beku, karena penurunan lemak lebih dari 5%. Kata kunci: penyimpanan beku, kadar lemak, surimi ikan ekor kuning.