With grass carp (Ctenopharyngodon idella) oil used as core material, chitosan (CTS) and soy protein isolate (SPI) as wall materials, CTS/SPI fish oil microcapsule product was prepared by use ultrasonic and spray drying. The embedding rate, particle size, thermal stability, storage stability, fish oil and microcapsule functional fatty acids content changes before and after storage and fall hematic fat action were studied. The results showed that the preparation of microcapsule embedding rate reached 77%, with the average particle size 15.8 μm, and the glass transition temperature (Tg) was 71 ℃. The functional fatty acids content changed little at 60 ℃, before and after 15 d storage. Feed the fish oil and fish oil microcapsule group of high density lipoprotein cholesterol (HDL-C) were significantly higher than the high fat model group, total cholesterol (TC) and low density lipoprotein cholesterol (LDL-C) were significantly lower than feeding high-fat model group, suggesting that fish oil microcapsules and fish oil could significantly reduce blood cholesterol.