A network terminal (1A-1H), comprising: communication means that communicates with other network terminals (1A-1H) connected via a network; time-series data creation means that, at timing set beforehand, creates time information including a correspondence between an identification number of the own network terminal and a current time measured by a timer of the own network terminal and creates time-series data registering the time information; additional registration means that, when the communication means receives the time-series data transmitted from another network terminal, creates time information including a correspondence between the identification number of the own network terminal and a current time measured by the timer of the own network terminal and additionally registers the time information to the time-series data received this time; transfer destination decision means that decides a network terminal as a transfer destination for each of time-series data created by the time-series data creation means and time-series data to which the additional registration means additionally registers time information; transfer means that, every time the transfer destination decision means decides a transfer destination of the time-series data, makes the communication means transfer the time-series data; determination means that determines that time-series data to which the time information is additionally registered by the additional registration means satisfies a time-setting condition when the number of network terminals registering the time information a plurality of times exceeds a threshold number of network terminals set beforehand; and time-setting means that, when the determination means determines that the time-setting condition is satisfied, performs time-setting by correcting a time measured by the timer of the own network terminal on a basis of time information registered in the time-series data, wherein the determination means determines that, when the number of network terminals registering the time information a plurality of times exceeds the threshold number of network terminals set beforehand in the time-series data, the time-setting condition is satisfied. communication means that communicates with other network terminals (1A-1H) connected via a network; time-series data creation means that, at timing set beforehand, creates time information including a correspondence between an identification number of the own network terminal and a current time measured by a timer of the own network terminal and creates time-series data registering the time information; additional registration means that, when the communication means receives the time-series data transmitted from another network terminal, creates time information including a correspondence between the identification number of the own network terminal and a current time measured by the timer of the own network terminal and additionally registers the time information to the time-series data received this time; transfer destination decision means that decides a network terminal as a transfer destination for each of time-series data created by the time-series data creation means and time-series data to which the additional registration means additionally registers time information; transfer means that, every time the transfer destination decision means decides a transfer destination of the time-series data, makes the communication means transfer the time-series data; determination means that determines that time-series data to which the time information is additionally registered by the additional registration means satisfies a time-setting condition when the number of network terminals registering the time information a plurality of times exceeds a threshold number of network terminals set beforehand; and time-setting means that, when the determination means determines that the time-setting condition is satisfied, performs time-setting by correcting a time measured by the timer of the own network terminal on a basis of time information registered in the time-series data, wherein the determination means determines that, when the number of network terminals registering the time information a plurality of times exceeds the threshold number of network terminals set beforehand in the time-series data, the time-setting condition is satisfied.