Abstract: In pH 5.9 NaAc-HAc buffer solution, neotamicin (NEO) interacts with sodium dodecyl benzene sulfate (SDB) to form ion association complex particles in size of about 160±12 nm. There are four RS peaks at 320, 340, 420 and 470 nm. The NEO concentration in the range of 0.076~6.840 μｇ/mL is proportional to the resonance scattering intensity at 470 nm. The detection limit is 0.03 μｇ/mL. The method has good selectivity and sensitivity, which can be applied to the determination of NEO in ear drips and urine samples, with satisfactory results.