Why are cats so afraid of cucumbers? It’s not that cats are afraid of cucumbers it’s their natural reaction to anything that sneaks up on them without making any noise. Cats tend to be scared or wary of the unknown, as it could represent the danger of a predator, and in the case of a cucumber, a snake. Cats are sharp and alert animals, and as such, they always keep their guard up and have good situational awareness. So, pretty much anything that sneaks up on a cat could potentially terrify it.