Syntheses of alkanosulfonylated starches are presented with alkane moiety being 1‐propyl‐, 1‐butyl‐, 1‐octyl, 1‐decyl‐ and 1‐octadecyl. Some properties of these compounds are described and results of their biological screening against Escherichia coli, Bacillus subtilis, Aspergillus niger and Aspergillus flavus are given.