The standard abstract
environment, when the titlepage
option is not given, just calls for a quotation
environment.
You can redefine the environment and use a customized list
environment instead.
The standard definition is equivalent to
\newenvironment{abstract}
{\small
\begin{center}
\bfseries \abstractname\vspace{-.5em}\vspace{0pt}
\end{center}
\quotation}
{\endquotation}
(unless the twocolumn
or titlepage
options are given).
For example, in order to have an indent by 5mm on each side, you can do
\renewenvironment{abstract}
{\small
\begin{center}
\bfseries \abstractname\vspace{-.5em}\vspace{0pt}
\end{center}
\list{}{%
\setlength{\leftmargin}{5mm}% <---------- CHANGE HERE
\setlength{\rightmargin}{\leftmargin}%
}%
\item\relax}
{\endlist}
Here's a complete example, where I also changed some of your calls.
\documentclass[a4paper,12pt]{article}
\usepackage[T1]{fontenc}
\usepackage[utf8]{inputenc}
\usepackage[margin=35mm]{geometry}% <-------- CHANGE HERE for the global margins
\usepackage{mathptmx} % for Times
\usepackage{graphicx} % for embedding pictures
\usepackage{lipsum} % just for the example
%\setlength{\parindent}{0mm} % Do not indent the 1st line of a paragraph.
%\setlength{\parskip}{3mm} % Add space between paragraphs.
\renewenvironment{abstract}
{\small
\begin{center}
\bfseries \abstractname\vspace{-.5em}\vspace{0pt}
\end{center}
\list{}{
\setlength{\leftmargin}{.5cm}%
\setlength{\rightmargin}{\leftmargin}%
}%
\item\relax}
{\endlist}
\begin{document}
\begin{abstract}
\lipsum*[2]
\end{abstract}
\lipsum[3]
\end{document}
You shouldn't use epsfig
, but graphicx
. Also geometry
is better than guessing at the page shape parameters. With this setting you get 35mm at each side of the paper, change to suit. Much more customizations are possible, see the manual.
Instead of times
(which is obsolete), call mathptmx
. For better results with math formulas, the combination
\usepackage{newtxtext,newtxmath}
might be preferred (I recommend it, instead of mathptmx
).
Please, don't do \setlength{\parindent}{0pt}
and \setlength{\parskip}{3mm}
; to begin with, the 3mm value is arbitrary and not tied to the font parameters. But the most important aspect is that these settings add white horizontal bands to each page that make it awful. And less legible.

epsfig
, it's an obsolete package that exists only for compatibility. If you're using a template for submitting your paper, you shouldn't change the setup, of course. – egreg Dec 28 '13 at 17:37\usepackage[margin=35mm]{geometry}
, which avoids guessing at the parameters. Don't usetimes
, butmathptmx
or, better,newtxtext
andnewtxmath
. – egreg Dec 28 '13 at 17:48\includegraphics
then (since I have removed epsfig and now I get errors) - isgraphicx
ok ?. And where should I put this\usepackage[margin=35mm]{geometry}
since I only want to change the margin of abstract bit? – Patryk Dec 28 '13 at 18:24graphicx
is the package to load. How would you change the abstract? – egreg Dec 28 '13 at 18:28