PROTAC PRMT1 degrader-1 (compound 4) is a PRMT1-targeting PROTAC degrader with an IC50 of 185.7 nM for human PRMT1. It recruits the CRBNE3 ubiquitin ligase, inducing proteasome-dependent degradation of PRMT1. Additionally, it forms a ternary complex with PRMT1 and CRBN, promoting PRMT1 ubiquitination followed by proteasomal degradation. This compound effectively reduces levels of asymmetrical dimethylarginine and asymmetrical dimethylation of histone H4 at arginine 3 in cancer cells while inhibiting the growth of various cancer cell lines. PROTAC PRMT1 degrader-1 is applicable in research on breast cancer and melanoma.