I add follow lines in .emacs: (add-to-list 'org-latex-classes '("thesis1" "\\documentclass{thesis1}" ("\\chapter{%s}" . "\\chapter*{%s}") ("\\section{%s}" . "\\section*{%s}") ("\\subsection{%s}" . "\\subsection*{%s}") ("\\subsubsection{%s}" . "\\subsubsection*{%s}") ("\\paragraph{%s}" . "\\paragraph*{%s}"))) ("\\subparagraph{%s}" . "\\subparagraph*{%s}"))) However it no works. The .tex have no subsubsection. Instead, it convert "**** XX" to "\item XX" in .tex file. Is the org export can only accept 3 section? How to resolve it? Thanks. Chen.