The levels of arylsulfatases A and B, $alpha$-amylase, aspartate transcarbamylase, and $gamma$-glutamyl transpeptidase were investigated during the infection of mice with schistosoma mansoni. This infection caused a significant (p<0.001) increase in the activity of hepatic arylsulfatase B (ASB), aspartate transcarbamylases and $gamma$-glutamyl transpeptidase. A non-significant difference occurred for $alpha$-amylase (p<0.3) and arylsulfatase A (p>0.5) when compared to the control. The specific activity of hepatic ASB was progressively increased with the progression of the Schistosoma-infection. Moreover, the kinetic studies of hepatic ASB in Schistosoma-infection showed that a slight decrease in the value of $K_m$ and about a 40% increase in $V_{max}$ when compared to the control. In addition, the pH optimum of hepatic ASB was altered from 6 to 7 as a result of schistosomiasis. These observations suggest that there are schistosomiasis-associated changes of the catalytic and kinetic properties of hepatic ASB.