Parsnip — Food safety facts
Safe to share · Cats · full breakdown on the linked food page
Cooked plain parsnip is safe in small pieces.
Short answer
Yes, plain cooked parsnip is safe for cats in small pieces. Steam or boil it without any seasoning, then chop into tiny portions. While not toxic, most cats won't show much interest in vegetables. Don't force it if your cat refuses — they're obligate carnivores after all.