\documentclass{book}
\usepackage{fancyhdr,graphicx}
\usepackage{xepersian}
% Save graphics in LaTeX box
\newsavebox{\mygraphic}
\sbox{\mygraphic}{\includegraphics[totalheight=0.5in]{kavir.jpg}}
\setlength{\headheight}{\dimexpr(\ht\mygraphic+3.60003pt)} %% must be large enough for graphic
\setlength{\textheight}{\dimexpr(\textheight-\ht\mygraphic-3.60003pt)}
\pagestyle{fancy}
\fancyhead{} % clear all header fields
\fancyhead[LO,RE]{\usebox{\mygraphic}}
\fancyfoot{} % clear all footer fields
\fancyfoot[C]{\thepage}
\renewcommand{\headrulewidth}{0.5pt}
\renewcommand{\footrulewidth}{0pt}
\makeatletter
\newcommand{\typesetfirsthundredpages}{%
\loop
\ifnum\c@page<101
این یک آزمایش  در صفحه \thepage{} است.
\newpage
\repeat}
\makeatother
\begin{document}
\typesetfirsthundredpages
\end{document}