One of the tilapia waste produced is offal. The content contained in the innards of tilapia contains a lot of fat which can be used as raw material for making fish oil. Fish oil plays an important role in health because it contains a source of omega 3. The application of fish oil into margarine can be used in the manufacture of bakery products. Making margarine requires an emulsion stability, which functions so that oil and water can mix. One of the emulsion stability that can be used is carrageenan. The purpose of this study was to determine the effect of using carrageenan on the stability of the emulsion on the physical properties of margarine and to determine the best concentration. This study used a completely randomized design (CRD), using one factor, namely the carrageenan concentration of 0.1; 0.2 and 0.3. The test parameters observed were water content test, spreadability test, texture test, melting point slip test, emulsion stability and hedonic test. The result shows that carrageenan plays a significant role as an emulsifier agent for the tilapia oil based margarine as it enhances the physical chracteristics of margarine. The best test results at a concentration of 0.3% with a water content value of 14.64%. The results for the basting power were 3.93%, while the slip melting point test was 33.80ᵒC, the stability test results were 93.07%, the hedonic test was 7.37 < µ < 7.76. The research suggests that there should be further analysis of margarine shelf-life time and fatty acid composition.