diff --git a/math/Makefile b/math/Makefile
index 9188af24b912..fc023f3f20af 100644
--- a/math/Makefile
+++ b/math/Makefile
@@ -274,6 +274,7 @@
     SUBDIR += numdiff
     SUBDIR += nyh-hoc
     SUBDIR += ocaml-ocamlgraph
+    SUBDIR += ocaml-zarith
     SUBDIR += ocamlgsl
     SUBDIR += octave
     SUBDIR += octave-forge
diff --git a/math/ocaml-zarith/Makefile b/math/ocaml-zarith/Makefile
new file mode 100644
index 000000000000..aa7d75d5ff7f
--- /dev/null
+++ b/math/ocaml-zarith/Makefile
@@ -0,0 +1,45 @@
+# Created by: John Marino <marino@FreeBSD.org>
+# $FreeBSD$
+
+PORTNAME=	zarith
+PORTVERSION=	1.2.1
+CATEGORIES=	math
+MASTER_SITES=	http://forge.ocamlcore.org/frs/download.php/1199/
+PKGNAMEPREFIX=	ocaml-
+
+MAINTAINER=	marino@FreeBSD.org
+COMMENT=	OCaml arithmetic library for arbitrary precision integers
+
+LICENSE=	GPLv2
+
+LIB_DEPENDS=	libgmp.so:${PORTSDIR}/math/gmp
+
+USES=			gmake perl5 shebangfix tar:tgz
+USE_PERL5=		build
+USE_OCAML=		yes
+USE_OCAML_FINDLIB=	yes
+OCAMLFIND_LDCONF=	/dev/null
+HAS_CONFIGURE=		yes
+ALL_TARGET=		all
+SHEBANG_FILES=		z_pp.pl
+CONFIGURE_ENV+=		DESTDIR=${STAGEDIR}
+CPPFLAGS+=		-I${LOCALBASE}/include
+LDFLAGS+=		-L${LOCALBASE}/lib
+
+MAKE_JOBS_UNSAFE=	yes
+PORTDOCS=	html
+DOCSDIR=	${OCAML_DOCSDIR}/${PORTNAME}
+
+OPTIONS_DEFINE=	DOCS
+
+.include <bsd.port.options.mk>
+
+.if ${PORT_OPTIONS:MDOCS}
+ALL_TARGET+= doc
+
+post-install:
+	${MKDIR} ${STAGEDIR}${DOCSDIR}
+	${MV} ${WRKSRC}/html ${STAGEDIR}${DOCSDIR}
+.endif
+
+.include <bsd.port.mk>
diff --git a/math/ocaml-zarith/distinfo b/math/ocaml-zarith/distinfo
new file mode 100644
index 000000000000..7acbd776f151
--- /dev/null
+++ b/math/ocaml-zarith/distinfo
@@ -0,0 +1,2 @@
+SHA256 (zarith-1.2.1.tgz) = 916801cc39599d3fca07384fbfeec4bfaa5ffcb497d68ef89320af40ba5e4144
+SIZE (zarith-1.2.1.tgz) = 68654
diff --git a/math/ocaml-zarith/files/patch-configure b/math/ocaml-zarith/files/patch-configure
new file mode 100644
index 000000000000..d8022f7de1b1
--- /dev/null
+++ b/math/ocaml-zarith/files/patch-configure
@@ -0,0 +1,26 @@
+--- configure.orig	2013-06-12 07:13:59.000000000 +0000
++++ configure
+@@ -304,6 +304,14 @@ case $host in
+             arch='i686'
+         fi
+ 	;;
++    i386-*freebsd* | i386-*dragonfly*)
++        ccdef="-DZ_ELF -DZ_DOT_LABEL_PREFIX $ccdef"
++        arch='i686'
++        ;;
++    amd64-*freebsd* | x86_64-*dragonfly*)
++        ccdef="-DZ_ELF -DZ_DOT_LABEL_PREFIX $ccdef"
++        arch='x86_64'
++        ;;
+     i386-*darwin* | x86_64-*darwin*)
+         ccdef="-DZ_UNDERSCORE_PREFIX -DZ_MACOS $ccdef"
+         if test "x$wordsize" = "x64"; then
+@@ -401,7 +409,7 @@ CFLAGS=$ccinc $ccdef $ccopt
+ ASFLAGS=$ccdef $asopt
+ LIBS=$cclib
+ ARCH=$arch
+-INSTALLDIR=$installdir
++INSTALLDIR=${DESTDIR}$installdir
+ AR=$ar
+ INSTALL=install
+ OCAMLFIND=ocamlfind
diff --git a/math/ocaml-zarith/pkg-descr b/math/ocaml-zarith/pkg-descr
new file mode 100644
index 000000000000..61b5b4c8d185
--- /dev/null
+++ b/math/ocaml-zarith/pkg-descr
@@ -0,0 +1,6 @@
+The Zarith library implements arithmetic and logical operations over
+arbitrary precision numbers.  It uses GMP to efficiently implement
+arithmetic over large numbers.  Small integers are represented as Caml
+unboxed integers for speed and space economy.
+
+WWW: http://forge.ocamlcore.org/projects/zarith
diff --git a/math/ocaml-zarith/pkg-plist b/math/ocaml-zarith/pkg-plist
new file mode 100644
index 000000000000..d050699b5e7d
--- /dev/null
+++ b/math/ocaml-zarith/pkg-plist
@@ -0,0 +1,15 @@
+%%OCAML_SITELIBDIR%%/zarith/META
+%%OCAML_SITELIBDIR%%/zarith/big_int_Z.cmi
+%%OCAML_SITELIBDIR%%/zarith/big_int_Z.mli
+%%OCAML_SITELIBDIR%%/zarith/dllzarith.so
+%%OCAML_SITELIBDIR%%/zarith/libzarith.a
+%%OCAML_SITELIBDIR%%/zarith/q.cmi
+%%OCAML_SITELIBDIR%%/zarith/q.mli
+%%OCAML_SITELIBDIR%%/zarith/z.cmi
+%%OCAML_SITELIBDIR%%/zarith/z.mli
+%%OCAML_SITELIBDIR%%/zarith/zarith.a
+%%OCAML_SITELIBDIR%%/zarith/zarith.cma
+%%OCAML_SITELIBDIR%%/zarith/zarith.cmxa
+%%OCAML_SITELIBDIR%%/zarith/zarith.cmxs
+%%OCAML_SITELIBDIR%%/zarith/zarith.h
+@dirrm %%OCAML_SITELIBDIR%%/zarith