This paper presents some results of quantity analysis phenol derivates in surface water. Surface water of Barnaul River in down stream and also Ob River in middle and down stream are chosen as an object of analysis. During spring high water was made the estimate influence organic matter on the chemical composition with the help of two independent methods: extraction photometric and voltammetry. The results of both methods are in close agreement within the bounds of accidental errors. For comparative analysis the distribution of "phenolic index" in the Ob River for autumnal low water is represented by authors.