A method and a user equipment for reporting a remaining delay budget information are provided. The method includes: receiving a radio resource control configuration, wherein the radio resource control configuration indicates the user equipment to report the remaining delay budget information of a logical channel or a logical channel group through a status report message; determining whether a triggering condition is met, wherein the triggering condition is associated with a threshold of remaining delay budget; and in response to the triggering condition being met, transmitting the status report message including the remaining delay budget information, wherein the remaining delay budget information indicates at least one remaining delay budget and at least one associated buffer size.