The invention discloses a buried pipeline system capable of monitoring the water inflow of a heat-insulation layer, and a preparation method thereof, belonging to the field of pipeline monitoring. Theburied pipeline system comprises a pipeline body, a heat-insulation layer wrapping the outer wall of the pipeline body, an outer protection layer wrapping the outer wall of the heat-insulation layer,a first monitoring module arranged between the pipeline body and the heat-insulation layer, a second monitoring module arranged between the heat-insulation layer and the outer protection layer, a first test lead hermetically passing through the outer protection layer and heat-insulation layer and then electrically connected with the first monitoring module, a second test lead hermetically passingthrough the outer protection layer and then electrically connected with the second monitoring module, and a multimeter electrically connected with the leading-out terminals, located out of the outerprotection layer, of the first test lead and the second test lead. According to the buried pipeline system provided by the invention, the first monitoring module and the second monitoring module madeof different metals are respectively installed on the inner side and the outer side of the heat-insulation layer, so whether water flows into the heat-insulation layer can be judged in time accordingto the potential difference between the first monitoring module and the second monitoring module.