Concentration of soluble proteins,soluble sugars and ions(Ca2+,Mg2+,Na+,Cl-and NO)derived from different tissues and organs was measured to evaluate the response of Apostichopus japonicus(Shuiyuan NO.1(Ss)and Dalian cultured(Ls)sea cucumber populations)to mild and acute temperature dropping(abbreviated as MTD and ATD)in laboratory.The initial temperature was set at 14°C and decreased from 8°C to-2°C by 2°C as a gradient,animals were prepared for further analysis after each temperature point decreased continually in 24h for MTD treatment and dropped sharply within 1.5h and maintained 12h.Results showed that the effects of the two cooling patterns on the concentration of soluble proteins,soluble sugars and different ions were significant.In MTD treatment,concentration of soluble proteins,soluble sugars and ions increased at first and decreased subsequently then increased to an unremarkable level or to a higher level compared to the initial level.However,in ATD treatment,the concentration showed a fluctuant variation tendency or decreased straightly with temperature dropping,this implied the damage caused by ATD is irreversible and thus more harmful to A.japonicas.Meanwhile,earlier response and faster self-adjusting ability were observed for Ss compared to Ls,which indicated a better cold tolerant ability for Ss.Such findings provide the basic scientific evidence for enriching the aquaculture techniques of A.japonicas,particularly for providing a new stress resistance trepang variety of A.japonicas culture in the farm pands.