The invention relates to a water quality turbidity calculating method based on ultraviolet-visible spectroscopy treatment. The method comprises the steps of (1) firstly, establishing a water sample feature library comprising spectrums of different water samples; (2) acquiring and detecting ultraviolet-visible spectrums of the water samples; (3) matching to obtain a sample spectrum which is most similar to a detected spectrum; (4) selecting the spectrum with the turbidity of 0 in the sample spectrum obtained by matching as a standard spectrum, and carrying out unary linear regression operation on the detected spectrum, the spectrums with other turbidities and the standard spectrum to obtain the translation and the inclined offset of all spectrum base lines; (5) correcting the detected spectrum to obtain a corrected spectrum curve; (6) fitting the translation of the base lines with the turbidities, and establishing a function relationship to obtain the turbidity value of the detected water sample. According to the method, the multiplicative scatter correction is used for correcting the spectrum curve, and the water quality turbidity can be worked out by fitting corrected parameters; furthermore, the influence caused by the turbidity is eliminated, the signal to noise ratio of a spectral signal is increased, and the help is provided for establishing a water quality parameter analysis model by adopting a stoichiometric method.