A yarn monitoring device that monitors a state of a yarn (Y) that travels in a traveling direction through a traveling space (R1, R2, R3) comprising: a housing ; and a yarn monitoring unit arranged inside the housing , wherein the yarn monitoring unit includes a monitoring section that monitors a state of the yarn (Y) that travels through the traveling space (R1, R2, R3); a yarn path guide that guides the traveling yarn (Y); and a holder that houses the monitoring section and the yarn path guide , wherein the yarn path guide is arranged adjacent to the traveling space (R1, R2, R3), characterized in that the yarn path guide includes a charge eliminating member that eliminates an electric charge generated by the traveling of the yarn (y), the housing includes a connecting member that is electrically connected to the charge eliminating member , and an electrical resistivity of the charge eliminating member is higher than or equal to an electrical resistivity of the connecting member wherein the connecting member is electrically connected to a ground potential, and wherein the yarn monitoring device further comprises a first electrically conductive member that is arranged in the housing ; and a substrate that sends information acquired by the monitoring section to the outside of the yarn monitoring device , and is electrically connected to a ground potential, wherein the connecting member is electrically connected to the substrate via the first electrically conductive member . a housing ; and a yarn monitoring unit arranged inside the housing , wherein the yarn monitoring unit includes a monitoring section that monitors a state of the yarn (Y) that travels through the traveling space (R1, R2, R3); a yarn path guide that guides the traveling yarn (Y); and a holder that houses the monitoring section and the yarn path guide , wherein a monitoring section that monitors a state of the yarn (Y) that travels through the traveling space (R1, R2, R3); a yarn path guide that guides the traveling yarn (Y); and a holder that houses the monitoring section and the yarn path guide , wherein the yarn path guide is arranged adjacent to the traveling space (R1, R2, R3), characterized in that the yarn path guide includes a charge eliminating member that eliminates an electric charge generated by the traveling of the yarn (y), the housing includes a connecting member that is electrically connected to the charge eliminating member , and an electrical resistivity of the charge eliminating member is higher than or equal to an electrical resistivity of the connecting member the housing includes a connecting member that is electrically connected to the charge eliminating member , and an electrical resistivity of the charge eliminating member is higher than or equal to an electrical resistivity of the connecting member wherein the connecting member is electrically connected to a ground potential, and wherein the yarn monitoring device further comprises a first electrically conductive member that is arranged in the housing ; and a substrate that sends information acquired by the monitoring section to the outside of the yarn monitoring device , and is electrically connected to a ground potential, wherein the connecting member is electrically connected to the substrate via the first electrically conductive member . a first electrically conductive member that is arranged in the housing ; and a substrate that sends information acquired by the monitoring section to the outside of the yarn monitoring device , and is electrically connected to a ground potential, wherein the connecting member is electrically connected to the substrate via the first electrically conductive member . <EOS>