A font library synchronization method, wherein the method is applied to a first terminal device, and the method comprises: identifying font library data information of font library data required for displaying a first message, wherein the first message is a message to be sent to a second terminal device; identifying, based on a font library synchronization record corresponding to the second terminal device, first font library data information of font library data that has not been synchronized to the second terminal device in the font library data information, wherein the font library synchronization record comprises font library data information of font library data that has been synchronized from the first terminal device to the second terminal device; and sending, to the second terminal device, first font library data corresponding to the first font library data information, wherein the method further comprises: receiving initial information sent by the second terminal device, wherein the initial information comprises initial font library data information of the second terminal device; determining an initial language of the second terminal device based on the initial information; when a current language of the first terminal device is inconsistent with the initial language of the second terminal device, generating second font library data based on the current language of the first terminal device and the initial information; and sending the second font library data to the second terminal device. identifying font library data information of font library data required for displaying a first message, wherein the first message is a message to be sent to a second terminal device; identifying, based on a font library synchronization record corresponding to the second terminal device, first font library data information of font library data that has not been synchronized to the second terminal device in the font library data information, wherein the font library synchronization record comprises font library data information of font library data that has been synchronized from the first terminal device to the second terminal device; and sending, to the second terminal device, first font library data corresponding to the first font library data information, wherein the method further comprises: receiving initial information sent by the second terminal device, wherein the initial information comprises initial font library data information of the second terminal device; determining an initial language of the second terminal device based on the initial information; when a current language of the first terminal device is inconsistent with the initial language of the second terminal device, generating second font library data based on the current language of the first terminal device and the initial information; and sending the second font library data to the second terminal device. receiving initial information sent by the second terminal device, wherein the initial information comprises initial font library data information of the second terminal device; determining an initial language of the second terminal device based on the initial information; when a current language of the first terminal device is inconsistent with the initial language of the second terminal device, generating second font library data based on the current language of the first terminal device and the initial information; and sending the second font library data to the second terminal device.