Jellyfish are one of the many hazards of the Hungry Shark series, and are in all of the installments, with the exception of Hungry Shark: Night. There are three different variations; the blue (normal) jellyfish, green (box) jellyfish and pink (moon) jellyfish, and all will spawn in various parts of the map. Blue jellyfish are the most common, green jellyfish are the second most common, and pink jellyfish are the rarest. Only blue and green jellyfish may be found in shallow water.thumb|400px|link=File:PJF.png
Jellyfish are dangerous, and will poison you on contact unless you buy the antidote power up from Hungry Shark Evolution in the store, or you can use the Megalodon, Robo Shark, Big Daddy, Mr Snappy the Great White and the Ice Shark (they are immune to all jellyfish, except the Great White and Ice Shark, they can eat only blue jellyfish).
In Hungry Shark Part 1, 2, and 3, eating jellyfish caused your health to decrease. In Hungry Shark Evolution, when your shark makes contact with a jellyfish, it will be stung and turn green for a few seconds. During these few seconds, your shark's health decreases at an accelerated rate, varying on the type of jellyfish. The blue jellyfish's poisonous effect is least harmful (dealing 7 damage per second), while the green's is the second most damaging (11 damage per second), and pink jellyfish's is the most damaging (18 damage per second).
Appearance in Hungry Shark World
In Hungry Shark World, Jellyfish appear in all of the usual types, but there is a difference in term of the types of shark which can eat them - Blue jellyfish can be eaten by XL sharks and above, Green by XXL sharks and above and Pink by !! sharks (additionally red if the player has the Atomic Shark). There is also two brand new types of Jellyfish, one of which appears in every ocean. The jellyfish mentioned to appear in every ocean are large, red coloured and cannot be eaten by any possible type of shark unless the Mega Gold Rush is active, or all of the HUNGRY letters have been collected. However, they can be eaten by the Atomic Shark without said Mega Gold Rush. The other new species of jellyfish is the King Jelly, which is an extremely large jellyfish exclusive to the South China Sea, cannot be eaten by ANY shark unless if you have Mega Gold Rush or HUNGRY letters, and tend to spawn with pink jellyfish in smaller quantities.
Red Jellyfish are also extremely deadly. Their poisonous effect causes a shark to lose health at very fast rate and for quite a long amount of time, killing smaller and even XL sharks after touching them once and bigger sharks after touching them 2, or 3 times. They should be avoided at all costs, since one mistake may spell shark's death.
King Jellies are even more deadly than red jellyfish. One sting can kill an !! shark without eating quickly. King Jellies should always be avoided and take note that sometimes more than one King Jelly can spawn in an area infested with pink jellyfish.
- Only the six sharks stated above can eat blue jellyfish; the Ice Shark, the Great White, the Robo Shark, the Megalodon, Big Daddy , Mr Snappy and the Electro shark
- The Megalodon, Robo Shark, Big Daddy and Mr Snappy can also eat pink and green jellyfish. Therefore, the sharks can't be stung by jellyfish at all.
- In previous versions of Hungry Shark Evolution, the Great White Shark could not eat blue jellyfish.
- Jellyfish actually restore health; they restore a minuscule 2 points of health, which is not noticeable. This was stated by Future Games of London on their Hungry Shark Evolution Facebook page. The exact value of 2 points is very, very little.
- Megalodon, Robo Shark, Big Daddy and Mr Snappy cannot use antidotes to defend against jellyfish as They're immune to them, and can eat them.
- There are two glitches about Blue Jellyfish size. One is some jellyfish are so little that they're very hard to notice, and the player could pass on them and get stung a lot without even noticing them (they can spawn in the Mako Shark drop point). The other one is some jellyfish are more than 8 meters long (bigger than a Tiger Shark) and they often completely block the access to some underwater caves (they usually spawn in deep and high water).
- Green Jellyfish are very hard to notice in shallow water, so Reef-Great White can get stung a lot and not notice it even if the jellyfish are big.
- Green jellyfish can be the size of a great white shark (glitch).
- While in the museum the reward is said to be "zero" that's not actually true: All kinds of jellyfish give a bit of points, and restore a tiny amount of points when eaten. This is probably an exaggeration.
- A glitch about pink jellyfish sizes are that they sometimes are bigger than a fully grown great white