A method of transmitting system information, a terminal and a network-side equipment are provided. The method includes: receiving, by a terminal, an SI change notification transmitted by a first network-side equipment; and receiving, by the terminal, SI transmitted by the first network-side equipment and corresponding to the SI change notification. And the SI change notification is carried in a DCI format corresponding to a PDCCH used for scheduling the paging message, or a DCI format corresponding to a PDCCH scrambled with C-RNTI.