Due to the harmful nature of 4,4'-diaminobiphenyl (DABP) to the environment and human health, the determination of DABP is of great significance and has received great attention. However, there is no electrochemical method reported to detect DABP. In this paper, perylenetetracarboxylic acid (PTCA) noncovalently functionalizes carbon nanohorns (PTCA-CNHs) nanohybrids were produced using a simple method and applied for the first electrochemical sensing of DABP. Herein, PTCA has two key advantages for functionalizing CNHs in DABP analysis: (I) PTCA could improve the dispersibility of CNHs in water and (II) enhance the accumulation capacity of DABP on PTCA-CNHs surface by means of the electrostatic interactions between PTCA (negative) and DABP (positive). The results show that the oxidation current of DABP at the PTCA-CNHs modified screen printed carbon electrode (SPCE) is much higher than that of the CNHs/SPCE and bare SPCE. The PTCA-CNHs/SPCE has a linear response range of 5.0 to 400.0 nM with a detection limit of 1.8 nM towards DABP detection.