可以重定义下 \tableofcontents
如下示例:
\documentclass{article}
\usepackage{multicol,xcolor}
\makeatletter
\setlength{\columnseprule}{1pt}
\renewcommand{\columnseprulecolor}{\color{green}}
\renewcommand\tableofcontents{%
\section*{\makebox[\linewidth][c]{\contentsname}%
\@mkboth{\MakeUppercase\contentsname}{\MakeUppercase\contentsname}}%
\begin{multicols}{2}%
\@starttoc{toc}%
\end{multicols}
}
\makeatother
\begin{document}
\tableofcontents
\section{test}
\section{another test}
\end{document}
效果如下: