  We successfully synthesized two new compounds Rb$_x$Fe$_{2-y}$S$_2$ and
Cs$_x$Fe$_{2-y}$S$_2$ which were isostructural with K$_x$Fe$_{2-y}$Se$_2$
superconductor. We systematically investigated the resistivity, magnetism and
thermoelectric power of $A_x$Fe$_{2-y}$S$_2$ ($A$=K, Rb and Cs) single
crystals. High temperature resistivity and magnetic measurements show anomalies
above 500 K depending on $A$ which are similar to $A_x$Fe$_{2-y}$Se$_2$.
Discrepancy between ZFC and FC curves was observed in K$_x$Fe$_{2-y}$S$_2$ and
Rb$_x$Fe$_{2-y}$S$_2$, while it disappears in Cs$_x$Fe$_{2-y}$S$_2$. Our
results indicate the similar magnetism between $A_x$Fe$_{2-y}$S$_2$ and
$A_x$Fe$_{2-y}$Se$_2$ at high temperature.
