diff --git a/sci-physics/lhapdf/lhapdf-6.5.5-r1.ebuild b/sci-physics/lhapdf/lhapdf-6.5.5-r1.ebuild
index af9fd6b5273b1..f3fa5dc2e648b 100644
--- a/sci-physics/lhapdf/lhapdf-6.5.5-r1.ebuild
+++ b/sci-physics/lhapdf/lhapdf-6.5.5-r1.ebuild
@@ -55,7 +55,7 @@ src_configure() {
 	local -x CONFIG_SHELL="${BROOT}/bin/bash"
 	econf \
 		--disable-static \
-		--with-yaml-cpp="${EPREFIX}/usr" \
+		--with-yaml-cpp="${ESYSROOT}/usr" \
 		$(use_enable python) \
 		$(use_enable doc doxygen)
 }
diff --git a/sci-physics/lhapdf/lhapdf-9999.ebuild b/sci-physics/lhapdf/lhapdf-9999.ebuild
index d3e5819a6d803..d8b9005b0cc58 100644
--- a/sci-physics/lhapdf/lhapdf-9999.ebuild
+++ b/sci-physics/lhapdf/lhapdf-9999.ebuild
@@ -61,7 +61,7 @@ src_configure() {
 	local -x CONFIG_SHELL="${BROOT}/bin/bash"
 	econf \
 		--disable-static \
-		--with-yaml-cpp="${EPREFIX}/usr" \
+		--with-yaml-cpp="${ESYSROOT}/usr" \
 		$(use_enable python) \
 		$(use_enable doc doxygen)
 }