Abstract: A slip test device includes a test member, a slip sensor, a pressing machine, a pressing force meter, a holding part, and a displacement meter. The pressing machine whose movement in a loading direction of the test member is constrained is configured to press a sample against a side of the test member that is an end portion of the test member in a direction perpendicular to the loading direction and with the sample sandwiched between the pressing machine and the test member. The holding part holds the sample between the test member and a pressing part. The pressing force meter measures a force with which the sample is pressed against the test member. The displacement meter measures the movement of the test member in the loading direction. The slip sensor measures a sliding motion of the sample in the loading direction relative to the pressing part or the test member.