diff --git a/lib/vagrant/util/ssh.rb b/lib/vagrant/util/ssh.rb
index 31356b094..a32125505 100644
--- a/lib/vagrant/util/ssh.rb
+++ b/lib/vagrant/util/ssh.rb
@@ -139,7 +139,8 @@ module Vagrant
             # Use '-o' instead of '-i' because '-i' does not call
             # percent_expand in misc.c, but '-o' does. when passing the path,
             # replace '%' in the path with '%%' to escape the '%'
-            command_options += ["-o", "IdentityFile=%s" % [path.to_s.gsub('%', '%%')]]
+            path = path.to_s.gsub('%', '%%')
+            command_options += ["-o", "IdentityFile=\"#{path}\""]
           end
         end
 
diff --git a/test/unit/vagrant/util/ssh_test.rb b/test/unit/vagrant/util/ssh_test.rb
index eb9da43d8..97de4f379 100644
--- a/test/unit/vagrant/util/ssh_test.rb
+++ b/test/unit/vagrant/util/ssh_test.rb
@@ -67,7 +67,7 @@ describe Vagrant::Util::SSH do
 
       expect(described_class.exec(ssh_info)).to eq(nil)
       expect(Vagrant::Util::SafeExec).to have_received(:exec)
-        .with("ssh", "vagrant@localhost", "-p", "2222", "-o", "LogLevel=FATAL","-o", "Compression=yes", "-o", "DSAAuthentication=yes", "-o", "StrictHostKeyChecking=no", "-o", "UserKnownHostsFile=/dev/null", "-o", "IdentityFile=#{ssh_info[:private_key_path][0]}")
+        .with("ssh", "vagrant@localhost", "-p", "2222", "-o", "LogLevel=FATAL","-o", "Compression=yes", "-o", "DSAAuthentication=yes", "-o", "StrictHostKeyChecking=no", "-o", "UserKnownHostsFile=/dev/null", "-o", "IdentityFile=\"#{ssh_info[:private_key_path][0]}\"")
     end
 
     context "when disabling compression or dsa_authentication flags" do
@@ -85,7 +85,7 @@ describe Vagrant::Util::SSH do
 
         expect(described_class.exec(ssh_info)).to eq(nil)
         expect(Vagrant::Util::SafeExec).to have_received(:exec)
-          .with("ssh", "vagrant@localhost", "-p", "2222", "-o", "LogLevel=FATAL", "-o", "StrictHostKeyChecking=no", "-o", "UserKnownHostsFile=/dev/null", "-o", "IdentityFile=#{ssh_info[:private_key_path][0]}")
+          .with("ssh", "vagrant@localhost", "-p", "2222", "-o", "LogLevel=FATAL", "-o", "StrictHostKeyChecking=no", "-o", "UserKnownHostsFile=/dev/null", "-o", "IdentityFile=\"#{ssh_info[:private_key_path][0]}\"")
       end
     end
 
@@ -103,7 +103,7 @@ describe Vagrant::Util::SSH do
 
         expect(described_class.exec(ssh_info)).to eq(nil)
         expect(Vagrant::Util::SafeExec).to have_received(:exec)
-          .with("ssh", "vagrant@localhost", "-p", "2222", "-o", "LogLevel=FATAL", "-o", "IdentityFile=#{ssh_info[:private_key_path][0]}")
+          .with("ssh", "vagrant@localhost", "-p", "2222", "-o", "LogLevel=FATAL", "-o", "IdentityFile=\"#{ssh_info[:private_key_path][0]}\"")
       end
     end
 
@@ -140,7 +140,7 @@ describe Vagrant::Util::SSH do
 
         expect(described_class.exec(ssh_info)).to eq(nil)
         expect(Vagrant::Util::SafeExec).to have_received(:exec)
-          .with("ssh", "vagrant@localhost", "-p", "2222", "-o", "LogLevel=FATAL", "-o", "StrictHostKeyChecking=no", "-o", "UserKnownHostsFile=/dev/null", "-o", "IdentityFile=#{ssh_info[:private_key_path][0]}","-o", "ForwardX11=yes", "-o", "ForwardX11Trusted=yes")
+          .with("ssh", "vagrant@localhost", "-p", "2222", "-o", "LogLevel=FATAL", "-o", "StrictHostKeyChecking=no", "-o", "UserKnownHostsFile=/dev/null", "-o", "IdentityFile=\"#{ssh_info[:private_key_path][0]}\"","-o", "ForwardX11=yes", "-o", "ForwardX11Trusted=yes")
       end
     end
 
@@ -158,7 +158,7 @@ describe Vagrant::Util::SSH do
 
         expect(described_class.exec(ssh_info)).to eq(nil)
         expect(Vagrant::Util::SafeExec).to have_received(:exec)
-          .with("ssh", "vagrant@localhost", "-p", "2222", "-o", "LogLevel=FATAL", "-o", "StrictHostKeyChecking=no", "-o", "UserKnownHostsFile=/dev/null", "-o", "IdentityFile=#{ssh_info[:private_key_path][0]}","-o", "ForwardAgent=yes")
+          .with("ssh", "vagrant@localhost", "-p", "2222", "-o", "LogLevel=FATAL", "-o", "StrictHostKeyChecking=no", "-o", "UserKnownHostsFile=/dev/null", "-o", "IdentityFile=\"#{ssh_info[:private_key_path][0]}\"","-o", "ForwardAgent=yes")
       end
     end
 
@@ -176,7 +176,7 @@ describe Vagrant::Util::SSH do
 
         expect(described_class.exec(ssh_info)).to eq(nil)
         expect(Vagrant::Util::SafeExec).to have_received(:exec)
-          .with("ssh", "vagrant@localhost", "-p", "2222", "-o", "LogLevel=FATAL", "-o", "StrictHostKeyChecking=no", "-o", "UserKnownHostsFile=/dev/null", "-o", "IdentityFile=#{ssh_info[:private_key_path][0]}", "-L", "8008:localhost:80")
+          .with("ssh", "vagrant@localhost", "-p", "2222", "-o", "LogLevel=FATAL", "-o", "StrictHostKeyChecking=no", "-o", "UserKnownHostsFile=/dev/null", "-o", "IdentityFile=\"#{ssh_info[:private_key_path][0]}\"", "-L", "8008:localhost:80")
       end
     end
 
@@ -194,7 +194,7 @@ describe Vagrant::Util::SSH do
 
         expect(described_class.exec(ssh_info)).to eq(nil)
         expect(Vagrant::Util::SafeExec).to have_received(:exec)
-          .with("ssh", "vagrant@localhost", "-p", "2222", "-o", "LogLevel=FATAL", "-o", "StrictHostKeyChecking=no", "-o", "UserKnownHostsFile=/dev/null", "-o", "IdentityFile=#{ssh_info[:private_key_path][0]}", "-6")
+          .with("ssh", "vagrant@localhost", "-p", "2222", "-o", "LogLevel=FATAL", "-o", "StrictHostKeyChecking=no", "-o", "UserKnownHostsFile=/dev/null", "-o", "IdentityFile=\"#{ssh_info[:private_key_path][0]}\"", "-6")
       end
     end