Improvement of frozen fishball quality by adding starch and / or pork back fat showed that frozen fishballs with the addition of 5 % tapioca or modified tapioca starch had no statistical significant difference in gel strength values and sensory scores. However, the addition of different levels of pork back fat in the samples caused significant difference in gel strength value. The higher the fat content the lower the gel strength value. During 3 months of frozen storage (-18 degree c), gel strength values of fishballs increased with time and sensory scores decreased. However, the addition of starch or starch plus fat in the product could extend these changes. Fishball with the addition of 5 % tapioca starch plus 4-8 % pork back fat could be kept frozen for 10 weeks with the acceptable sensory scores. Scanning Electron Microscope (SEM) was used to study the microstructure of comminuted fish meat prepared at different steps of the fishball process. Surimi micrograph of batter, that chopped with salt, starch and pork back fat showed the interconnected network of protein matrix. Cooking the meat batter caused the matrix to become more aggregated and occured as opaque gel, and the fat globules were bound to the protein gel matrix.