diff --git a/lib/resty/healthcheck.lua b/lib/resty/healthcheck.lua
index 739301b1..1d7daa19 100644
--- a/lib/resty/healthcheck.lua
+++ b/lib/resty/healthcheck.lua
@@ -38,6 +38,8 @@ local resty_lock = require ("resty.lock")
 local re_find = ngx.re.find
 local bit = require("bit")
 local ngx_now = ngx.now
+local pl_file = require("pl.file")
+local ssl = require("ngx.ssl")
 
 -- constants
 local EVENT_SOURCE_PREFIX = "lua-resty-healthcheck"
@@ -829,8 +831,16 @@ function checker:run_single_check(ip, port, hostname, hostheader)
 
   if self.checks.active.type == "https" then
     local session
-    session, err = sock:sslhandshake(nil, hostname,
+    if self.ssl_cert and self.ssl_key then
+      session, err = sock:tlshandshake({
+        verify = self.checks.active.https_verify_certificate,
+        client_cert = self.ssl_cert,
+        client_priv_key = self.ssl_key
+      })
+    else
+      session, err = sock:sslhandshake(nil, hostname,
                                      self.checks.active.https_verify_certificate)
+    end
     if not session then
       sock:close()
       self:log(ERR, "failed SSL handshake with '", hostname, " (", ip, ":", port, ")': ", err)
@@ -1339,6 +1349,12 @@ function _M.new(opts)
   self.shm = ngx.shared[tostring(opts.shm_name)]
   assert(self.shm, ("no shm found by name '%s'"):format(opts.shm_name))
 
+  -- load certificate and key
+  if opts.ssl_cert and opts.ssl_key then
+    self.ssl_cert = assert(ssl.parse_pem_cert(pl_file.read(opts.ssl_cert, true)))
+    self.ssl_key = assert(ssl.parse_pem_priv_key(pl_file.read(opts.ssl_key, true)))
+  end
+
   -- other properties
   self.targets = nil     -- list of targets, initially loaded, maintained by events
   self.events = nil      -- hash table with supported events (prevent magic strings)
diff --git a/t/17-mtls.t b/t/17-mtls.t
new file mode 100644
index 00000000..ad0a2407
--- /dev/null
+++ b/t/17-mtls.t
@@ -0,0 +1,114 @@
+use Test::Nginx::Socket::Lua;
+use Cwd qw(cwd);
+
+workers(1);
+
+plan tests => repeat_each() * 3;
+
+my $pwd = cwd();
+
+our $HttpConfig = qq{
+    lua_package_path "$pwd/lib/?.lua;;";
+    lua_shared_dict test_shm 8m;
+    lua_shared_dict my_worker_events 8m;
+};
+
+run_tests();
+
+__DATA__
+
+=== TEST 1: configure a MTLS probe
+--- http_config eval
+qq{
+    $::HttpConfig
+}
+--- config
+    location = /t {
+        content_by_lua_block {
+            local we = require "resty.worker.events"
+            assert(we.configure{ shm = "my_worker_events", interval = 0.1 })
+            local healthcheck = require("resty.healthcheck")
+            local checker = healthcheck.new({
+                name = "testing_mtls",
+                shm_name = "test_shm",
+                type = "http",
+                ssl_cert = "t/util/cert.pem",
+                ssl_key = "t/util/key.pem",
+                checks = {
+                    active = {
+                        http_path = "/status",
+                        healthy  = {
+                            interval = 999, -- we don't want active checks
+                            successes = 3,
+                        },
+                        unhealthy  = {
+                            interval = 999, -- we don't want active checks
+                            tcp_failures = 3,
+                            http_failures = 3,
+                        }
+                    },
+                    passive = {
+                        healthy  = {
+                            successes = 3,
+                        },
+                        unhealthy  = {
+                            tcp_failures = 3,
+                            http_failures = 3,
+                        }
+                    }
+                }
+            })
+            ngx.say(checker ~= nil)  -- true
+        }
+    }
+--- request
+GET /t
+--- response_body
+true
+
+=== TEST 2: fail to configure a MTLS probe
+--- http_config eval
+qq{
+    $::HttpConfig
+}
+--- config
+    location = /t {
+        content_by_lua_block {
+            local we = require "resty.worker.events"
+            assert(we.configure{ shm = "my_worker_events", interval = 0.1 })
+            local healthcheck = require("resty.healthcheck")
+            local checker = healthcheck.new({
+                name = "testing_mtls",
+                shm_name = "test_shm",
+                type = "http",
+                ssl_cert = "t/util/wrongcert.pem",
+                ssl_key = "t/util/wrongkey.pem",
+                checks = {
+                    active = {
+                        http_path = "/status",
+                        healthy  = {
+                            interval = 999, -- we don't want active checks
+                            successes = 3,
+                        },
+                        unhealthy  = {
+                            interval = 999, -- we don't want active checks
+                            tcp_failures = 3,
+                            http_failures = 3,
+                        }
+                    },
+                    passive = {
+                        healthy  = {
+                            successes = 3,
+                        },
+                        unhealthy  = {
+                            tcp_failures = 3,
+                            http_failures = 3,
+                        }
+                    }
+                }
+            })
+        }
+    }
+--- request
+GET /t
+--- error_code: 500
diff --git a/t/util/cert.pem b/t/util/cert.pem
new file mode 100644
index 00000000..2df6a75a
--- /dev/null
+++ b/t/util/cert.pem
@@ -0,0 +1,19 @@
+-----BEGIN CERTIFICATE-----
+MIIDCTCCAfGgAwIBAgIUWWntedJ1yLAJE2baK/Mg06osmGAwDQYJKoZIhvcNAQEL
+BQAwFDESMBAGA1UECgwJS29uZyBJbmMuMB4XDTIwMDQyMzIwMjcwMFoXDTMwMDQy
+MTIwMjcwMFowFDESMBAGA1UECgwJS29uZyBJbmMuMIIBIjANBgkqhkiG9w0BAQEF
+AAOCAQ8AMIIBCgKCAQEAvVBrEH34MzwKlkBapiNyXr9huSShuojy+7i/01BSFng3
+1TiejXJ3pEjykZqt7ENkZ6+BTYUdb9klK221yXiSyX71x97O0WHHuhH/m4XwGiIH
+YPBHdg+ExdMRflXgwtlW3of2hTWxkPkPQDPhoSQVMc5DkU7EOgrTxkv1rUWVAed4
+gSK4IT2AkhKwOSkewZANj2bnK5Evf71ACyJd7IQbJAIYoKBwRJAUXJMA7XAreIB+
+nEr9whNYTklhB4aEa2wtOQuiQubIMJzdOryEX5nufH+tL4p1QKhRPFAqqtJ2Czgw
+YZY/v9IrThl19r0nL7FIvxFDNIMeOamJxDLQqsh9NwIDAQABo1MwUTAdBgNVHQ4E
+FgQU9t6YAdQ5mOXeqvptN5l3yYZGibEwHwYDVR0jBBgwFoAU9t6YAdQ5mOXeqvpt
+N5l3yYZGibEwDwYDVR0TAQH/BAUwAwEB/zANBgkqhkiG9w0BAQsFAAOCAQEAhi83
+aXsfJGqr9Zb1guWxbI8uKoG6o88ptXjV2c6dJnxXag0A/Rj+bX2bcPkN2kvQksNl
+MBUQlniOydZfsBUAoC0V7yyGUv9eO2RIeFnnNpRXNu+n+Kg2bvgvu8BKNNNOASZv
++Vmzvo9lbfhS9MNAxYk9eTiPNUZ3zn2RfFyT6YWWJbRjk//EAlchyud3XGug9/hw
+c05dtzWEYT8GdzMd+Y1/2kR5r/CapSj7GEqL5T3+zDIfjbhTokV7WBrw6og2avoZ
+vzrF8xWucry5/2mKQbRxMyCtKYUKTcoLzF4HrNQCETm0n9qUODrHER7Wit9fQFZX
+1GEA3BkX2tsbIVVaig==
+-----END CERTIFICATE-----
diff --git a/t/util/key.pem b/t/util/key.pem
new file mode 100644
index 00000000..ae945f44
--- /dev/null
+++ b/t/util/key.pem
@@ -0,0 +1,28 @@
+-----BEGIN PRIVATE KEY-----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+-----END PRIVATE KEY-----