Kim, who signed a two-year, $7 million contract with the Orioles last December, must agree to any minor league assignment.
"Yes, it looks like he's not going to be on the 25-man roster to start the season," Orioles executive Dan Duquette said Tuesday.
Kim began the spring without a hit in his first 23 at-bats and is batting .182 without an extra-base hit.
"I think in these cases the transition takes some time," Duquette said. "I believe he wants to give it some more time."
When approached by reporters on Sunday, Kim said he was happy he signed with Baltimore.
Over the weekend, manager Buck Showalter said that he hadn't made up his mind about Kim.
"He's competing," Showalter said. "We'll see what the next few days bring. We've got some tough decisions to make."