diff --git a/plugins/provisioners/ansible/provisioner/host.rb b/plugins/provisioners/ansible/provisioner/host.rb
index 2bc67c3fe..ac5b8b2db 100644
--- a/plugins/provisioners/ansible/provisioner/host.rb
+++ b/plugins/provisioners/ansible/provisioner/host.rb
@@ -255,7 +255,7 @@ module VagrantPlugins
           # Multiple Private Keys
           unless !config.inventory_path && @ssh_info[:private_key_path].size == 1
             @ssh_info[:private_key_path].each do |key|
-              ssh_options << "-o IdentityFile=%s" % [ key.gsub('%', '%%') ]
+              ssh_options << "-o 'IdentityFile=%s'" % [ key.gsub('%', '%%') ]
             end
           end