Is it possible to get it without using package titletoc? I'm using special chapter style which doesn't work with this package.

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And the tocloft package is an option? –  Gonzalo Medina May 19 '12 at 22:27
Yes, it's possible. Perhaps provide further information, such as you preamble or even better a small compilable example with your class, packages and settings. –  Stefan Kottwitz May 19 '12 at 22:28

There are so many options... without further information, one possible option would be to use the setspace package and one of its commands of environments; for example,

\documentclass{report}
\usepackage{setspace}

\begin{document}

\doublespacing
\tableofcontents
\singlespacing

\chapter{Test Chapter One}
\section{Test Section One One}
\section{Test Section One Two}
\chapter{Test Chapter Two}
\section{Test Section Two One}
\section{Test Section Two Two}

\end{document}


This approach will increase evenly the space between all sectional units. The following three options allow you to control separately the spacing for each group of sectional units.

Another option would be to use the tocloft package and redefine the \cftXafterpnum family of commands:

\documentclass{report}
\usepackage{tocloft}

\renewcommand\cftchapafterpnum{\vskip10pt}
\renewcommand\cftsecafterpnum{\vskip15pt}

\begin{document}

\tableofcontents

\chapter{Test Chapter One}
\section{Test Section One One}
\section{Test Section One Two}
\chapter{Test Chapter Two}
\section{Test Section Two One}
\section{Test Section Two Two}

\end{document}


Yet another option, this time using the etoolbox package to patch the sectional units commands to add vertical space to the ToC:

\documentclass{report}
\usepackage{etoolbox}

\makeatletter
\makeatother

\begin{document}

\tableofcontents

\chapter{Test Chapter One}
\section{Test Section One One}
\section{Test Section One Two}
\chapter{Test Chapter Two}
\section{Test Section Two One}
\section{Test Section Two Two}

\end{document}


A fourth option not requiring any packages would be to redefine the \chapter and \section commands as implemented in the used document class to add the vertical space to the ToC; an example with report:

\documentclass{report}

\makeatletter
\if@openright\cleardoublepage\else\clearpage\fi
\thispagestyle{plain}%
\global\@topnum\z@
\@afterindentfalse
\secdef\@chapter\@schapter}
\@startsection {section}{1}{\z@}%
{-3.5ex \@plus -1ex \@minus -.2ex}%
{2.3ex \@plus.2ex}%
{\normalfont\Large\bfseries}}
\makeatother

\begin{document}

\tableofcontents

\chapter{Test Chapter One}
\section{Test Section One}
\section{Test Section Two}
\chapter{Test Chapter One}
\section{Test Section One}
\section{Test Section Two}

\end{document}


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Thank you for detailed answer. –  Jane May 20 '12 at 12:12

While the other suggestions so far allow increasing the line spacing of the Table of Contents, it seems they don't allow decreasing it, for example to fit a ToC on one page.

A simple

\renewcommand{\baselinestretch}{0.75}\normalsize
\tableofcontents
\renewcommand{\baselinestretch}{1.0}\normalsize


will allow setting any line spacing.

It might be necessary to find out what your baselinestretch size is by default as the style seems to set this.

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Using tocloft, you can also add the following in your preamble to add spacing before a section entry:

\usepackage{tocloft}

\setlength{\cftbeforesecskip}{6pt}


This complements Gonzalo's Answer in where he shows how to add spacing after a section entry: that can be undesirable in case you have subsections following a section. The tocloft's manual has many other options that can be used to manipulate other types of entries in the TOC.

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