A method for controlling a network connection of a wireless network device, comprising: before a portion of operations of the wireless network device enters a sleep mode and a wireless network of the wireless network device is disconnected: setting a tag to indicate if a connected access point has a security setting or not; storing information of a current network connection between the wireless network device and the connected access point as a pre-stored network connection information if the connected access point does not have a security setting; after a portion of the wireless network device is woken up from the sleep mode: resuming an operating system of the wireless network device; loading a wireless network driver by the operating system; and characterized by: utilizing the pre-stored network connection information to determine whether the previous connected access point has the security setting or not by checking the tag; and when the tag indicates that the previous connected access point does not have the security setting, the wireless network driver directly utilizes the pre-stored network connection information to connect to the previous connected access point without scanning the access points to obtain an IP address through a dynamic host configuration protocol, DHCP, and checking if the connection status is correct or incorrect; when the tag indicates that the previous connected access point has the security setting or when the connection status is incorrect, the wireless network driver scans the access points to obtain at least one access point, the operating system receives the at least one access point and chooses one access point, and the operating system sends the chosen access point to the wireless network driver to establish a link. setting a tag to indicate if a connected access point has a security setting or not; storing information of a current network connection between the wireless network device and the connected access point as a pre-stored network connection information if the connected access point does not have a security setting; after a portion of the wireless network device is woken up from the sleep mode: resuming an operating system of the wireless network device; loading a wireless network driver by the operating system; and characterized by: utilizing the pre-stored network connection information to determine whether the previous connected access point has the security setting or not by checking the tag; and when the tag indicates that the previous connected access point does not have the security setting, the wireless network driver directly utilizes the pre-stored network connection information to connect to the previous connected access point without scanning the access points to obtain an IP address through a dynamic host configuration protocol, DHCP, and checking if the connection status is correct or incorrect; when the tag indicates that the previous connected access point has the security setting or when the connection status is incorrect, the wireless network driver scans the access points to obtain at least one access point, the operating system receives the at least one access point and chooses one access point, and the operating system sends the chosen access point to the wireless network driver to establish a link. resuming an operating system of the wireless network device; loading a wireless network driver by the operating system; and characterized by: utilizing the pre-stored network connection information to determine whether the previous connected access point has the security setting or not by checking the tag; and when the tag indicates that the previous connected access point does not have the security setting, the wireless network driver directly utilizes the pre-stored network connection information to connect to the previous connected access point without scanning the access points to obtain an IP address through a dynamic host configuration protocol, DHCP, and checking if the connection status is correct or incorrect; utilizing the pre-stored network connection information to determine whether the previous connected access point has the security setting or not by checking the tag; and when the tag indicates that the previous connected access point does not have the security setting, the wireless network driver directly utilizes the pre-stored network connection information to connect to the previous connected access point without scanning the access points to obtain an IP address through a dynamic host configuration protocol, DHCP, and checking if the connection status is correct or incorrect; when the tag indicates that the previous connected access point has the security setting or when the connection status is incorrect, the wireless network driver scans the access points to obtain at least one access point, the operating system receives the at least one access point and chooses one access point, and the operating system sends the chosen access point to the wireless network driver to establish a link.