\documentclass[12pt,a4paper]{article}
\usepackage[T2A]{fontenc}
\usepackage[cp1251]{inputenc}
\usepackage[russian]{babel}
\renewcommand{\thesubsection}{\arabic{subsection}}
\begin{document}
\subsection{первый}
text text text
\subsection{второй}
text text text
\end{document}
为此,重新定义显示计数器值的命令就足够了
\thesubsection:\renewcommand{\thesubsection}{\arabic{subsection}}