Abstract: Folic acid is an important vitamin in human body.In dialy diet，intaking quantity of folic acid is not enough.Exploring method of rapid detection folic acid is of great significance for detecting raw materials of food and developing functional products rich in folic acid.In this research，folic acid solution with 20 concentration gradients was prepared.Transmission spectrum were acquired by visible-near infrared spectrometer.Folic acid solution was analyzed by two-dimensional correlation spectrum theory and the concentration was regarded as external disturbance.Results showed that there were three characteristic spectrums，from strong to weak，430，450 and 550 nm in visible region.Absorbance values at these bands were linearly dependent on the concentration of folic acid solution，and correlation coefficients were above 0.98.There were six characteristic spectrums，from strong to weak，1 410，1 440，1 490，1 540，1 520 and 1 510 nm in short wave near infrared spectrum region.In this study，sensitive band and sensitive degree of folic acid solution were pointed out under action of visible-near infrared transmission spectrum.It will be helpful for rapid detection of folic acid.