The invention discloses a combined conversion socket with a cigarette lighter plug, wherein a first housing and a second housing of an electrocircuit are respectively arranged inside the socket, a first prong of a first specification standard contacted with the internal circuit is arranged on one side of the first housing and a second plug jack of a second specification standard conducted with the internal circuit is arranged on the other side of the first housing, a second prong of a second specification standard contacted with the internal circuit is arranged on one side of the second housing and a second plug jack of a first specification standard conducted with the internal circuit is arranged on the other side of the second housing, a USB socket and a cigarette lighter plug connected with the internal circuit of the housing are also arranged on the second housing. Prongs or plug jacks of different specification standards are arranged on different sides of the housing, which is convenient for people to use electric apparatus with different socket standards. The USB socket facilitates the usage of electric products. The arrangement of the cigarette lighter plug and the plug for aircraft expands the function of the combined conversion socket.