Sardine (Sardina pilchardus) surimi gels set (50°C or 60°C), or set and cooked (50°C or 60°C + 90°C) for different times were studied in order to evaluate modori (thermal gel degradation). The texture data of the set gels were similar to data obtained previously in gels set at lower temperature that produced good kamaboko gels. However, in gels set at 50°C and 60°C modori occurred upon cooking. Microscopically the set gels exhibited globular aggregated structures that became more compact when modori occurred. Results suggested that at modori temperature protein-protein bonding caused massive protein coagulation preventing the formation of a fibrillar matrix upon cooking.