diff --git a/devel/Makefile b/devel/Makefile
index 6be11230feb03..703b2868cedb7 100644
--- a/devel/Makefile
+++ b/devel/Makefile
@@ -7724,6 +7724,7 @@
     SUBDIR += undead
     SUBDIR += unibilium
     SUBDIR += universal-ctags
+    SUBDIR += unordered-dense
     SUBDIR += upnp
     SUBDIR += upp
     SUBDIR += upslug
diff --git a/devel/unordered-dense/Makefile b/devel/unordered-dense/Makefile
new file mode 100644
index 0000000000000..63f9e6e3e39fb
--- /dev/null
+++ b/devel/unordered-dense/Makefile
@@ -0,0 +1,26 @@
+PORTNAME=	unordered-dense
+DISTVERSIONPREFIX=	v
+DISTVERSION=	4.0.4
+CATEGORIES=	devel
+
+MAINTAINER=	yuri@FreeBSD.org
+COMMENT=	Fast & densely stored hashmap and hashset
+WWW=		https://github.com/martinus/unordered_dense
+
+LICENSE=	MIT
+LICENSE_FILE=	${WRKSRC}/LICENSE
+
+USES=		cmake compiler:c++17-lang
+
+USE_GITHUB=	yes
+GH_ACCOUNT=	martinus
+GH_PROJECT=	${PORTNAME:S/-/_/}
+
+PLIST_FILES=	include/ankerl/unordered_dense.h \
+		lib/cmake/unordered_dense/unordered_denseConfig.cmake \
+		lib/cmake/unordered_dense/unordered_denseConfigVersion.cmake \
+		lib/cmake/unordered_dense/unordered_denseTargets.cmake
+
+NO_ARCH=	yes
+
+.include <bsd.port.mk>
diff --git a/devel/unordered-dense/distinfo b/devel/unordered-dense/distinfo
new file mode 100644
index 0000000000000..f7e3ba6487b35
--- /dev/null
+++ b/devel/unordered-dense/distinfo
@@ -0,0 +1,3 @@
+TIMESTAMP = 1690361383
+SHA256 (martinus-unordered_dense-v4.0.4_GH0.tar.gz) = b34a8c942963e3a647f1bbc192a6391cd56d7ae615b2ddc1601c1779b5792206
+SIZE (martinus-unordered_dense-v4.0.4_GH0.tar.gz) = 365284
diff --git a/devel/unordered-dense/pkg-descr b/devel/unordered-dense/pkg-descr
new file mode 100644
index 0000000000000..4409793a15f9a
--- /dev/null
+++ b/devel/unordered-dense/pkg-descr
@@ -0,0 +1,2 @@
+unordered-dense implements a fast & densely stored hashmap and hashset based on
+robin-hood backward shift deletion for C++17 and later.