Anti‐CD19, CD20, CD22, CD7, and BCMA CAR‐T have been applied to treat B‐cell or T‐cell hematological tumors and multiple myeloma.[2, 17] This study selected the classical anti‐CD19 CAR (CAR19) as a paradigm to screen CAR‐binding aptamers. The gene discussed is CD7; the disease is plasma cell myeloma.