Mesothelin (MSLN) is an attractive therapeutic target for precision cancer treatments. Here, we identify a MSLN-targeting DARPin, M7, which specifically binds to the protease-sensitive C-terminal region of MSLN. Furthermore, we develop two auristatin-based DARPin-drug conjugates (DARPin-DCs), M7A-DC and M7GA-DC. We show that M7A-DC and M7GA-DC are effectively internalized by MSLN-positive cells, leading to the release of MMAE that induces lethal effects on tumor cells and bystander killing against MSLN-negative cells. Both M7A-DC and M7GA-DC induce long-lasting tumor regression with favorable tolerability in mice.