The present invention relates to a rainwater infiltration device. The purpose of the present invention is to provide the rainwater infiltration device capable of installing a filtering module only using a simple structure and being easily installed even when the height of the installation space varies. To achieve the same, the rainwater infiltration device wherein the filtering unit is installed is composed of: a base installed in a clastic unit on the ground and including an inner vertical through-hole; a filtering unit receiving unit installed on the top of the base and including a vertical filtering unit through-hole; and the filtering unit installed on the upper part of the base inside the filtering unit receiving unit. The filtering unit receiving unit is characterized by including multiple unit receiving unit modules capable of being vertically stacked one after another. The rainwater infiltration device according to the present invention is capable of supporting the filtering unit without a separate device or a separate facility, thereby obtaining an effect of simplifying the structure of the device and an effect of being easily manufactured. In addition, the height of the rainwater infiltration device is easily adjusted to be easily installed even when the height of the installation space varies.
