diff --git a/manila_tempest_tests/tests/scenario/manager_share.py b/manila_tempest_tests/tests/scenario/manager_share.py
index fd02db0..4e0c1b7 100644
--- a/manila_tempest_tests/tests/scenario/manager_share.py
+++ b/manila_tempest_tests/tests/scenario/manager_share.py
@@ -132,7 +132,10 @@
         return share_network
 
     def boot_instance(self, wait_until="ACTIVE"):
-        self.keypair = self.create_keypair()
+        # In case of multiple instances, use a single keypair to prevent a keys
+        # mismatch.
+        if not hasattr(self, 'keypair'):
+            self.keypair = self.create_keypair()
         security_groups = [{'name': self.security_group['name']}]
         create_kwargs = {
             'key_name': self.keypair['name'],
diff --git a/releasenotes/notes/bug-1858024-fa76d4c5b27f099b.yaml b/releasenotes/notes/bug-1858024-fa76d4c5b27f099b.yaml
new file mode 100644
index 0000000..b94e1c9
--- /dev/null
+++ b/releasenotes/notes/bug-1858024-fa76d4c5b27f099b.yaml
@@ -0,0 +1,8 @@
+---
+fixes:
+  - |
+    Fixed bug #1858024. Define a signle key for multiple instances.
+    Currently every instance initialization creates a unique keypair.
+    An unnecessary resource duplication, when a single user boots more
+    than one instance.
+    Depending on test flow this may also cause keypair mismatch.