In the title molecule, C18H23NO3, the hydroperoxybutyl substituent is nearly fully extended, with the four torsion angles in the range 170.23 (10)–178.71 (9)°. The O—O distance in the hydroperoxide group is 1.4690 (13) Å. This group acts as an intermolecular hydrogen-bond donor to a quinoline N atom. This results in dimeric units about the respective inversion centers, with graph-set notation R
2
2(18)