Although tetrodotoxin (TTX) is an extremely neuro-toxic compound, its activities have potential applications as medicines. There must be an efficient antidote for this toxin to minimize risks in clinical trial as well as in poisoning from TTX consumption. Therefore, screening for compounds which can neutralize, detoxify the toxicity of TTX or reduce its negative effects is necessary. Previous studies showed that hemolymph from Carcinoscorpius rotundicauda containing TTX binding protein could detoxify TTX in mice. This study investigated for binding protein as well as TTX detoxification capability of Tachypleus tridentatus hemolymph to hypothesize the main role in TTX detoxification. The result of this study illustrated that hemolymph Tachypleus tridentatus with the dose less than 20mg protein per mouse unit showed no capability in TTX detoxification even though there was survival prolong insignificantly. The study also checked hemolymph Carcinoscorpius rotundicauda, showing there was no capability in TTX detoxification. A major protein of hemolymph, purified hemocyanin also had no activity in TTX detoxification. In summary, TTX detoxification in capability in TTX detoxification was not due to hemolymph or hemocyanin