سلام
بصورت زیر:
\documentclass[12pt,a4paper]{report}
\usepackage{graphicx}
\usepackage{caption}
\usepackage{subcaption}
\begin{document}
\begin{figure}[ht]
\begin{subfigure}[b]{0.3\textwidth}
\centering
\includegraphics[width=.85\linewidth]{example-image-a}
\caption{A gull}
\label{fig:gull}
\end{subfigure}%
\begin{subfigure}[b]{0.3\textwidth}
\centering
\includegraphics[width=.85\linewidth]{example-image-a}
\caption{A gull2}
\label{fig:gull2}
\end{subfigure}%
\begin{subfigure}[b]{0.3\textwidth}
\centering
\includegraphics[width=.85\linewidth]{example-image-a}
\caption{A tiger}
\label{fig:tiger}
\end{subfigure}%
\caption{Pictures of animals}\label{fig:animals}
\end{figure}
\end{document}
خروجی:
قرار دادن 6 تصویر به صورت 2*3 :
روش 1:
\documentclass[12pt,a4paper]{report}
\usepackage{graphicx}
\begin{document}
\begin{figure}[ht]
\centering
\includegraphics[width=.3\textwidth]{example-image-b}\quad
\includegraphics[width=.3\textwidth]{example-image-b}\quad
\medskip
\includegraphics[width=.3\textwidth]{example-image-b}\quad
\includegraphics[width=.3\textwidth]{example-image-b}
\medskip
\includegraphics[width=.3\textwidth]{example-image-b}\quad
\includegraphics[width=.3\textwidth]{example-image-b}
\caption{Figure caption}
\label{pics:blablabla}
\end{figure}
\end{document}
روش 2:
\documentclass[12pt,a4paper]{report}
\usepackage{graphicx}
\begin{document}
\begin{figure}[ht]
{\centering%
\begin{tabular}{@{}cc@{}}
\includegraphics[width=50mm]{example-image-b}&
\includegraphics[width=50mm]{example-image-b}
\end{tabular}\par}
{\centering%
\begin{tabular}{@{}cc@{}}
\includegraphics[width=50mm]{example-image-b}&
\includegraphics[width=50mm]{example-image-b}
\end{tabular}\par}
{\centering%
\begin{tabular}{@{}cc@{}}
\includegraphics[width=50mm]{example-image-b}&
\includegraphics[width=50mm]{example-image-b}
\end{tabular}
\caption{Figure caption}
\label{pics:blablabla}\par}
\end{figure}
\end{document}
خروجی:
توجه: بهتره که subfig.pdf رو مطالعه کنید.
در پرسش زیر هم هستش:
http://qa.parsilatex.com/9613/
http://qa.parsilatex.com/2562/
موفق باشید.