The present invention relates to a sampler which is capable of rapidly and easily separating blood corpuscles from blood, being operated conveniently, and directly using extracted plasma. According to one embodiment of the present invention, a sampler includes a chamber and a membrane guide. Here, the chamber includes an insertion unit having an insertion hole on one side, wherein the other side is opened, and an inner side includes a receiving space for receiving a sample. Additionally, one side of the membrane guide is combined to the membrane, and the membrane guide includes a channel wherein filtered materials, which are filtered through the membrane among the samples received in the receiving space, are moved in a gravitational direction.