Paras locations — where to catch

In Hisui (Legends: Arceus)

• Cloudpool Ridge — Walk
• Cottonsedge Prairie — Walk
• Diamond Heath — Walk
• Droning Meadow — Walk
• Golden Lowlands — Walk
• Heavenward Lookout — Walk
• Nature's Pantry — Walk
• Ursa's Ring — Walk
• Wayward Wood — Walk
• Windbreak Stand — Walk

In Sinnoh (Diamond, Pearl & Platinum)

• Great Marsh — Walk

In Johto & Kanto (HeartGold & SoulSilver)

• Ilex Forest — Walk
• Johto Safari Zone — Walk
• Mt. Moon — Walk
• National Park — Walk

In Kanto (FireRed & LeafGreen)

• Mt. Moon — Walk
• Safari Zone — Walk

In Johto & Kanto (Gold, Silver & Crystal)

• Ilex Forest — Walk
• Mt. Moon — Walk
• National Park — Bug-Catching Contest

In Kanto (Red, Blue & Yellow)

• Mt. Moon — Walk
• Safari Zone — Walk

Other games (8)

• Brilliant Diamond / Shining Pearl (Gen 8): Great Marsh
• Let's Go, Pikachu! / Let's Go, Eevee! (Gen 7): Mt Moon
• Ultra Sun / Ultra Moon (Gen 7): Brooklet Hill, Lush Jungle
• Sun / Moon (Gen 7): Alola Route 11, Brooklet Hill, Lush Jungle
• Omega Ruby / Alpha Sapphire (Gen 6): Petalburg Woods
• X / Y (Gen 6): Friend Safari
• Black / White (Gen 5): Route 11
• XD (Gen 3): Cipher Key Lair

Paras — full Pokédex entry