Hole-transporting layer (HTL) is one of the key components in a regular perovskite solar cell (r-PSC), which has the function of extracting the photon-excited holes from the absorber and then transporting them to the electrode. The most commonly used HTL in r-PSC is LiTFSI and tBP-doped spiro-OMeTAD. The inevitable instability induced by a deliquescent inorganic salt (LiTFSI), the migration of small lithium ions, and the necessary oxidation process in air hinder the commercialization of this technology. In this paper, a new undoped D-A copolymer