A message keeping method performed by at least one processor of a device includes receiving a selection input of at least one first message from among a plurality of messages included in a first chatroom, adding, based on the selection input, the at least one first message to a kept message list to be displayed in the first chatroom, and sending, to a second chatroom and based on the selection input, a second message associated with the at least one first message and including original content of the at least one first message and a link addressed to the first chatroom. The second chatroom is dedicated to message keeping.