A network connection establishment method (100, 200, 500), wherein the method comprises: establishing (S101, S201, S501), by a first device, a data channel with a second device based on an universal serial bus, USB, interface between the first device and the second device, wherein the data channel is adapted to transmit data according to an USB video class, UVC, protocol; updating (S102, S202, S502), by the first device, a session key based on a preset period; receiving (S103, S203, S503), by the first device, an obtaining request from the second device through the data channel; sending (S104, S204, S504), by the first device in response to the obtaining request, a first session key to the second device through the data channel, wherein the first session key is a latest session key when the first device receives the obtaining request; establishing (S105, S205, S505), by the first device, a first network channel with the second device based on the USB interface between the first device and the second device, wherein the network channel is adapted to transmit data according to a TCP/IP protocol; if a second session key is received through the first network channel within first preset duration, detecting (S106, S208, S508), by the first device, whether the second session key is the same as the first session key; and if the second session key is the same as the first session key, sending (S107, S208, S512), by the first device, response information to the second device through the first network channel, wherein the response information is information used by the first device to respond to a request sent by the second device through the first network channel. establishing (S101, S201, S501), by a first device, a data channel with a second device based on an universal serial bus, USB, interface between the first device and the second device, wherein the data channel is adapted to transmit data according to an USB video class, UVC, protocol; updating (S102, S202, S502), by the first device, a session key based on a preset period; receiving (S103, S203, S503), by the first device, an obtaining request from the second device through the data channel; sending (S104, S204, S504), by the first device in response to the obtaining request, a first session key to the second device through the data channel, wherein the first session key is a latest session key when the first device receives the obtaining request; establishing (S105, S205, S505), by the first device, a first network channel with the second device based on the USB interface between the first device and the second device, wherein the network channel is adapted to transmit data according to a TCP/IP protocol; if a second session key is received through the first network channel within first preset duration, detecting (S106, S208, S508), by the first device, whether the second session key is the same as the first session key; and if the second session key is the same as the first session key, sending (S107, S208, S512), by the first device, response information to the second device through the first network channel, wherein the response information is information used by the first device to respond to a request sent by the second device through the first network channel.