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White spot occurred on the shell of white shrimp (Litopenaeus vannamei) shell during frozen storage was proved to be due to calcium carbonate precipitation, and continuously expand covered the entire transparent shell. This research aimed to study the effect of some chemical treatment before freezing on quality and white spot occurrence on the shell of frozen white shrimp. The results indicated that treatment with different chemical solution i.e. sodium metabisulphite 4.3%, citric acid 0.075%, pyrophosphate 0.5% and sodium chlorine 23% gave different effect on white spot formation. The initial frozen white shrimp showed a lower tendency of white spot formation than those products kept for 1-2 months. Treatment with pyrophosphate and citric acid solution prior to freezing retarded white spot index (p<0.05) while treatment with sodium metabisulphite solution promoted the white spot index. From these findings, it can be concluded that calcium carbonate precipitation resulting in white spots in shrimp shell can be retarded or possibly prevented by short storage time and chemical treatment.