A polyelectrolyte composition is represented by the following formula (1). In the formula (1), R1 is hydrogen or CH3, R2 is any of C2H4, CH(CH3)CH2, and (CH2)3, m and n are each a copolymerization ratio of a structural unit in parentheses, and when m and n are set as follows: m+n=10, m and n satisfy the following formulae: 1≤m≤5 and 5≤n≤9, and p is 2 or more and 8 or less.