Application of 6 different herbicides in potato cultivation resulted in changes of chemical composition of tubers, quality of chips and properties of starch. Sencor, Bladex, Topogard, Afalon and Aresin indicated rather unfavourable effects on chemical composition of the tubers. On one hand they increased the average weight of the tubers, on the other hand they decreased the dry matter (triazines) and starch content (Afalon). They increased the amount of reducing and total sugars (urea) and increased the content of amide nitrogen (triazines and Afalon) and amino acid nitrogen (Bladex). Sencor and Afalon resulted in darker colour of the chips. Afalon, Aresin and Chwastox increased the part of small granules or decreased the amount of large granules in the starch. Afalon and Bladex resulted in changes of phosphorus content, and Chwastox changed the amount of amylose in starch.