The 21-year-old joins Palace on a two-year deal, after a spell at Portsmouth last season.
She began her career at the Brighton & Hove Albion Academy, where she had loan spells at Hibernian and Plymouth Argyle.
Erhabor joined Portsmouth in July 2025 and made six appearances for the club in all competitions.
Born in the Netherlands and raised in England, Erhabor represents the Nigeria national team.
She made her Super Falcons debut in February, starting in a friendly against Cameroon ahead of her inclusion in Nigeria’s squad for the 2026 Women's Africa Cup of Nations.
Manager Jo Potter said: “Comfort is a promising young goalkeeper, and we are thrilled to have her here at Palace.”
Erhabor said: “It feels really good to be here. I'm very excited to get started.
"I'm aspiring to play at the highest level, so this is a really big step in my career."