Abstract: A self-made FI-fiber-absorption spectrometric automatic analyzer was applied to the determination of formaldehyde in textiles. The color-reaction of formaldehyde with acetylacetone was completed in the flow injection system,with (w) 0.5% of acetylaceton and at 80 ℃. The absorbance of the color system was measured at its maximum absorption wavelength of 414 nm. Linear relationship between values of absorbance and mass concentration of formanldehyde was obtained in the range of 0.025-3.00 mg·L-1,with detection limit (3S/N) of 0.025 mg·L-1. Precision of the method was tested at the concentration level of 1.00 mg·L-1 formanldehyde standard solution for 10 determination,value of RSD found was 0.95%. The proposed method was applied to the analysis of textile samples,giving results in consistency with the values obtained by the GB method. Values of recovery found was in the range of 96.5%-117%.