Skip to Content

What is deadliest animal on earth?

Determining the deadliest animal on earth is not a simple task. There are many factors to consider when evaluating the danger posed by different animal species. However, by looking at criteria like the number of human deaths caused annually and the lethality of venom or toxins, we can develop a good sense of which animals are among the most deadly.

Key Factors in Deadliness

Two of the most important factors are:

  • The number of human deaths caused per year – High death tolls indicate a deadly threat
  • Venom/toxin lethality – Extremely toxic venoms that are frequently delivered can cause more deaths

Other considerations include aggressiveness, distribution, human encroachment into habitats, and size/strength. However, the animals that kill the most people annually and have the most potent toxins rise to the top of the list.

The Deadliest Animals:


When looking at the raw number of human deaths caused annually, the mosquito tops the list. Mosquitos transmit a variety of deadly diseases, including:

  • Malaria – Over 600,000 deaths per year, mostly in Africa
  • Dengue Fever – 40,000 deaths per year
  • Yellow Fever – 30,000 deaths per year
  • Zika Virus – Thousands of deaths and birth defects
  • West Nile Virus – Over 1,000 deaths per year
  • Chikungunya – Causing sporadic epidemics
  • Other diseases like encephalitis

The World Health Organization estimates mosquitos cause over 1 million human deaths per year. This staggering death toll is why the mosquito can be considered the world’s deadliest animal.


Humans are without a doubt one of the deadliest animals on the planet when looking at our history of violence towards each other. Some of the death toll estimates include:

  • At least 108 million violent war deaths over written history
  • Over 1.6 million homicide deaths per year currently
  • Over 450,000 homicide deaths since 2000 in Latin America/Caribbean alone
  • Tens of millions more from systemic issues like poverty and malnutrition

No other species comes close to inflicting this level of death and suffering within its own species.


Venomous snakes account for tens of thousands of deaths per year worldwide. Some of the deadliest include:

  • Saw-scaled Viper – Over 5,000 deaths per year, primarily in India.
  • Common Krait – Thousands of deaths per year in South Asia.
  • Russell’s Viper – Over 1,000 deaths annually in Asia.
  • Eastern Brown Snake – The deadliest snake in Australia.
  • Black Mamba – Extremely lethal venom, but antivenom available.
  • Taipan Snakes – Among the most toxic venoms on earth.

Snakes deliver fast-acting hemotoxic and neurotoxic venoms that can kill quickly. Antivenoms prevent many more deaths where available.


Along with spiders, scorpions account for a significant number of deaths due to venomous stings and bites each year:

  • Over 1,000 deaths annually from scorpion stings
  • Deadliest species include the Deathstalker, Arizona Bark Scorpion, and Androctonus
  • Lethal neurotoxins and hemotoxins in venom
  • Most lethal in regions with limited medical care

Scorpions are found on every continent except Antarctica and can be hazardous in remote areas far from hospitals.

Other Deadly Animals

Here are some other animals that can claim many human lives each year or possess extremely toxic venoms/toxins:

  • Crocodiles – Over 1,000 deaths annually
  • Elephants and Hippos – Hundreds of deaths per year
  • Cape Buffalo – Very aggressive, kill over 200 people a year in Africa
  • Lions – Up to 100 fatal attacks on humans per year
  • Box Jellyfish – Extremely venomous, up to 100 deaths annually
  • Sharks – Kill less than 10 people per year on average
  • Blue-ringed Octopus – Highly venomous with no antivenom
  • Stonefish – Very toxic venom that can kill untreated
  • Africanized Bees – Highly aggressive with lethal venom

Large aggressive animals and those with highly neurotoxic venoms all pose major dangers to human life regularly.

The Deadliest Animal Depends on Criteria

In summary, there are a few standout animals that can be considered the deadliest based on different criteria:

  • Mosquitos kill the most humans per year by far
  • Humans have caused the most historical deaths within a species
  • Snakes account for tens of thousands of deaths annually
  • Scorpions and spiders kill thousands per year
  • Large predators like crocodiles and lions prey on humans
  • Toxic marine species can kill extremely quickly

So while the mosquito is likely the overall deadliest due to disease transmission, other animals rank high for their lethal venoms or for causing significant annual human deaths through predation or defensive aggression. Determining the deadliest animal is ultimately subjective based on the criteria used.


Evaluating what is the world’s deadliest animal involves analyzing different factors like annual human deaths, toxicity of venom, historical violence, and more. The mosquito is arguably the overall deadliest animal due to the massive numbers of deaths caused by the diseases it spreads. However, many other animals can also lay claim to being among the most deadly species on earth depending on the specific criteria used. These include snakes, scorpions, crocodiles, hippos, lions, and humans ourselves. Determining the deadliest animal is ultimately complex with no universally agreed upon answer across all categories.