The Scottish SPCA is appealing for information after the cats were believed to have been poisoned by anti-freeze.
All three cats are from Mains Road in Dundee and one of the animals was put down after displaying symptoms of poisoning.
Scottish SPCA Inspector Robert Baldie said that the charity had also received reports of cats in the area going missing.
He added: "We have received reports that three cats in the area have been victims of poisoning and that others have gone missing.
"Sadly, one cat had to be put to sleep and a post mortem has confirmed that it died from anti-freeze poisoning.
"Two other cats have also shown symptoms consistent with poisoning. It is possible that the poisonings could be accidental so we would ask motorists to ensure that anti-freeze is stored carefully to avoid leaks or spillages.
"However, it may be that these poisonings have been deliberate, which is a real cause for concern. Poisoning causes an animal an extremely painful death so we would advise cat owners in the area to be vigilant and report anything suspicious."
Anyone found guilty of deliberately poisoning an animal can face a jail sentence, a fine of up to £20,000, or both.
If you have information regarding the poisonings, you should call the Scottish SPCA Animal Helpline on 03000 999 999.