Objective Understand the formaldehyde content of dehydrated aquatic products sold by Tangshan.Methods There were 4 kinds of dehydrated aquatic products from 4 regions of Tangshan contained 101 samples being collected.The determination of formaldehyde content used the acetylacetone spectrophotometry ruled by aquaculture industry standard of China of SC/T 3025—2006.Use SPSS13.0 statistical software for data analysis.This study used the limit(30mg/kg) that recommended by Liu Shuling[1] as a standard to calculate the failure rate.Results The formaldehyde was relatively general in dry aquatic products and its detection rate was 100%.The formaldehyde content was in the range of 0.75~483.26 mg/kg.In all the samples,there were 30 samples containing formaldehyde over 30mg/kg and its rate was 29.70%.The highest formaldehyde content of the samples was dried shrimp and the lowest was dried prawn.The differences were statistically significant after analyzing the formaldehyde failure rate of different kinds of samples.The formaldehyde content of software dry products was the highest.Conclusion The quality of dehydrated aquatic products sold by Tangshan was good,but there were some samples like dried shrimps didn’t remove the possibility of increasing formaldehyde by people.