YTHu78 is a KDM5B PROTAC-based degrader. It induces the degradation of KDM5B through the ubiquitin-proteasome system and triggers apoptosis in MV-4-11 and MM.1S cell lines. YTHu78 demonstrates significant antiproliferative activity against various hematologic tumor cell lines and is useful for studying hematological malignancies.