Ethanolic extracts from coconut husk (EECH) could be used as the potential cross-linkers for strengthening the gel of yellowfin tuna swim bladder gelatin. EECH was able to increase gel strength most effectively when it was added at a level of 0.5 mg g−1. EECH at an excessive amount (5 mg g−1) showed the negative impact on gel strength. EECH incorporation at 0.5 mg g−1 did not cause the changes in color of resulting gelatin gel.