Where do you catch a meowth in Pokemon diamond?

Answer 1

its a good idea to get either Pokemon leafgreen or firered and catch meowth there. from there, you can migrate meowth once you have completed the shinnoh podex. proffeser oak will come, give you a national podex and he'll tell you to go to the pal park (to go there, you need to take the route on the beach in sandgment town and use surf). You can also rarely get one at the trophy garden if Mr. Backlot says he saw one in the garden.

Catching it in the trophy garden isn't hard, it just takes a long time. So if you're too impatient, just get FireRed or LeafGreen.

You go to route 212 (south of Hearthome City) and go to the mansion there. Go inside and go down the hallway on the right. Save. Go in the first door and talk to the man in front of you. He is Mr. Backlot. When you talk to him, just answer yes to everything and if he doesn't say anything about a Meowth, turn off and back on and try again. This should work, but it only appears 5% of the time. If he talks about the same Pokemon, try again tomorrow.
Once you get the National Dex (A Dex you can fill with all 493 Pokemon.), go to the Pokemon Mansion, north of Hearthome City, and speak to Mr. Backlot, he'll either say he saw an Eevee, Porygon, Meowth, Happiny, Mime Jr., Bonsly, or Igglybuff. The Pokemon stays in Trophy Garden even if he says it's a different Pokemon. For example:

when he says he found a Meowth and once you find Meowth in the Trophy Garden with a Pokeradar then the next day later when he says he found a Eevee, Meowth will still be able to be found in Trophy Garden.

Hope this helped!