Absolute absorption cross sections of the absorption spectrum of the 2ν₁ band of the HO₂ radical in the near-IR region were measured by continuous wave cavity ring-down spectroscopy (cw-CRDS) coupled to laser photolysis in the wavelength range 6604−6696 cm^-1 with a resolution better than 0.003 cm^-1. Absolute absorption cross sections were obtained by measuring the decay of the HO₂ self-reaction, and they are given for the 100 most intense lines. The most important absorption feature in this wavelength range was found at 6638.20 cm^-1, exhibiting an absorption cross section of σ = 2.72 × 10^-19 cm² at 50 Torr He. Using this absorption line, we obtain a detection limit for the HO₂ radical at 50 Torr of 6.5 × 10¹⁰ cm^-3.