diff --git a/macros.rubygems b/macros.rubygems
index 532ea6c..2552780 100644
--- a/macros.rubygems
+++ b/macros.rubygems
@@ -60,7 +60,7 @@ gem install \\\
 #
 %gemspec_add_dep(g:s:d) \
 read -d '' gemspec_add_dep_script << 'EOR' || : \
-  gemspec_file = '%{-s*}%{!?-s:%{_builddir}/%{gem_name}-%{version}.gemspec}' \
+  gemspec_file = '%{-s*}%{!?-s:%{_builddir}/%{gem_name}-%{version}%{?prerelease}.gemspec}' \
   \
   name = '%{-g*}' \
   requirements = %{*}%{!?1:nil} \
@@ -97,7 +97,7 @@ unset -v gemspec_add_dep_script \
 #
 %gemspec_remove_dep(g:s:d) \
 read -d '' gemspec_remove_dep_script << 'EOR' || : \
-  gemspec_file = '%{-s*}%{!?-s:%{_builddir}/%{gem_name}-%{version}.gemspec}' \
+  gemspec_file = '%{-s*}%{!?-s:%{_builddir}/%{gem_name}-%{version}%{?prerelease}.gemspec}' \
   \
   name = '%{-g*}' \
   requirements = %{*}%{!?1:nil} \
@@ -144,7 +144,7 @@ unset -v gemspec_remove_dep_script \
 #
 %gemspec_add_file(s:tr) \
 read -d '' gemspec_add_file_script << 'EOR' || : \
-  gemspec_file = '%{-s*}%{!?-s:%{_builddir}/%{gem_name}-%{version}.gemspec}' \
+  gemspec_file = '%{-s*}%{!?-s:%{_builddir}/%{gem_name}-%{version}%{?prerelease}.gemspec}' \
   \
   abort("gemspec_add_file: Use only one '-t' or '-r' at a time.") if "%{?-t}%{?-r}" == "-t-r" \
   \
@@ -177,7 +177,7 @@ unset -v gemspec_add_file_script \
 #
 %gemspec_remove_file(s:tr) \
 read -d '' gemspec_remove_file_script << 'EOR' || : \
-  gemspec_file = '%{-s*}%{!?-s:%{_builddir}/%{gem_name}-%{version}.gemspec}' \
+  gemspec_file = '%{-s*}%{!?-s:%{_builddir}/%{gem_name}-%{version}%{?prerelease}.gemspec}' \
   \
   abort("gemspec_remove_file: Use only one '-t' or '-r' at a time.") if "%{?-t}%{?-r}" == "-t-r" \
   \
diff --git a/ruby.spec b/ruby.spec
index 511448a..e09834e 100644
--- a/ruby.spec
+++ b/ruby.spec
@@ -1203,6 +1203,8 @@ OPENSSL_SYSTEM_CIPHERS_OVERRIDE=xyz_nonexistent_file OPENSSL_CONF='' \
 * Thu Jul 04 2019 Jun Aruga <jaruga@redhat.com> - 2.6.3-106
 - Use ffi_closure_alloc to avoid segmentation fault by libffi on aarch64.
   Resolves: rhbz#1727832
+- Properly support %%prerelease in %%gemspec_ macros.
+  Related: rhbz#1672575
 
 * Tue Jun 11 2019 Jun Aruga <jaruga@redhat.com> - 2.6.3-105
 - Update to Ruby 2.6.3 by merging Fedora master branch (commit: 1cc2a49)