Coastal Taipan. That would be incorrect though. Fierce Snake or Inland Taipan, which is very closely related to the Coastal Taipan, has the most potent venom in the world. Maximum yield recorded (for one bite) is 110mg. That would probably be enough to kill over 100 people or 250,000 mice. That's just 1 bite.

And Saw Scaled Viper's have venom 16 times more potent then Russell's Viper, and they are responsible for more deaths in Africa then all the other venomous African snakes combined.

The Tiger snake however is a very aggressive snake and kills more people in Australia then any other venemous snake.

The Malayan Krait has a 50% fatality rate even WITH antivenin treatment.