Abstract: A new record genus and a new record species (Ancyrocephalidae, Monogenea) from China are recorded for the first time. Lethrinitrema Lim & Justine, 2011 and Lethrinitrema gibbus Lim & Justine,2011 parasitized on gills of Lethrinus xanthochilus. Members of Lethrinitrema are characterized by having two pyriform haptoral reservoirs and ventral anchors with lateral grooves. The elongating tubular distal end of each reservoir bifurcates, draining into a superficial lateral groove on each side of the ventral anchors. Morphology and size of our specimens are basically in accordance with the origin description of Lim & Justine (2011). Lethrinitrema gibbus is the new record of host.