A mobile network hotspot sharing method includes starting hotspot sharing, receiving, from a hotspot access device for a shared hotspot and after starting the hotspot sharing, a connection request, performing authentication on the connection request, and after the authentication on the connection request succeeds, allowing the hotspot access device to access the shared hotspot. Then, the hotspot sharing device receives data from the hotspot access device, and sends the data using an uplink network interface card of the shared hotspot, where the uplink network interface card includes a subscriber identity module (SIM) card that has activated mobile network data and that is in the hotspot sharing device, and the SIM card includes a non-default data service card.