Why is my cat not eating? It’s common that your cat is not eating the offered food. Maybe they are sleepy or simply to put it out they’re being picky. However, if that is happening on a regular basis then it should be taken into consideration. There can be numerous reasons your cat is not eating on time. Most cat owners are not aware of the fact that cats are good at hiding illness which can be a reason for your cat not eating on time or they have been recently vaccinated.