A user equipment (UE) and a method for system information (SI) modification and acquisition procedure are provided. The method includes receiving downlink control information (DCI) with a cyclic redundancy check (CRC) scrambled by a paging radio network temporary identifier (P-RNTI) from a base station, the DCI including an SI modification bit and a public warning system (PWS) notification bit; performing an SI acquisition procedure upon determining that the SI modification bit is set; and acquiring at least one of an earthquake and tsunami warning system (ETWS) notification and a commercial mobile alert system (CMAS) notification upon determining that the PWS notification bit is set.