diff --git a/tools/harness-sniffer/OT_Sniffer.py b/tools/harness-sniffer/OT_Sniffer.py
new file mode 100644
index 000000000..3df900a5b
--- /dev/null
+++ b/tools/harness-sniffer/OT_Sniffer.py
@@ -0,0 +1,156 @@
+#!/usr/bin/env python
+#
+# Copyright (c) 2019, The OpenThread Authors.
+# All rights reserved.
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions are met:
+# 1. Redistributions of source code must retain the above copyright
+#    notice, this list of conditions and the following disclaimer.
+# 2. Redistributions in binary form must reproduce the above copyright
+#    notice, this list of conditions and the following disclaimer in the
+#    documentation and/or other materials provided with the distribution.
+# 3. Neither the name of the copyright holder nor the
+#    names of its contributors may be used to endorse or promote products
+#    derived from this software without specific prior written permission.
+#
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+# AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+# ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
+# LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+# CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+# SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+# INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+# CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+# ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+# POSSIBILITY OF SUCH DAMAGE.
+
+''''OpenThread Sniffer API implementation'''
+
+import os
+import subprocess
+from GRLLibs.UtilityModules.ModuleHelper import ModuleHelper
+from ISniffer import ISniffer
+
+
+class OT_Sniffer(ISniffer):
+    def __init__(self, **kwargs):
+        try:
+            self.channel = kwargs.get('channel', 11)
+            self.port = kwargs.get('addressofDevice')
+            self.subprocess = None
+            self.is_active = False
+
+        except Exception as e:
+            ModuleHelper.WriteIntoDebugLogger('OT_Sniffer: [intialize] --> ' + str(e))
+
+    def discoverSniffer(self):
+        sniffers = []
+
+        p_discover = subprocess.Popen('extcap_ot.bat --extcap-interfaces', stdout=subprocess.PIPE, shell=True)
+        for line in p_discover.stdout.readlines():
+            if line.startswith('interface'):
+                try:
+                    # e.g. interface {value=COM10:460800}{display=OpenThread Sniffer COM10}
+                    interface_port = line[line.index('value=') + 6 : line.index('}{display')]
+                    sniffers.append(OT_Sniffer(addressofDevice=interface_port, channel=ModuleHelper.Default_Channel))
+                except Exception as e:
+                    ModuleHelper.WriteIntoDebugLogger('OT_Sniffer: [discoverSniffer] --> Error: ' + str(e))
+
+        p_discover.wait()
+        return sniffers
+
+    def startSniffer(self, channelToCapture, captureFileLocation):
+        """
+        Method for starting the sniffer capture on given channel and this should create wireshark 'pcapng' file at the
+        given location. Capture should happen in background so that method call will be non-blocking and asynchronous.
+        @param channelToCapture : int : channel number to start the capture
+        @param captureFileLocation : string : Full path with the filename with extension is passed.
+        """
+        try:
+            # start sniffer
+            self.setChannel(channelToCapture)
+            p_where = subprocess.Popen(
+                'py -3 -c "import sys; print(sys.executable)"', stdout=subprocess.PIPE, shell=True,
+            )
+            # python_exe: e.g. C:\Python37\python.exe
+            python_exe = p_where.stdout.readline().strip()
+
+            if python_exe.endswith(".exe"):
+                # sniffer_py: e.g. C:\Python37\Scripts\sniffer.py
+                sniffer_py = str(os.path.dirname(python_exe)) + '\\Scripts\\sniffer.py'
+
+                cmd = [
+                    python_exe,
+                    sniffer_py,
+                    '-c',
+                    str(self.channel),
+                    '-u',
+                    str(self.port.split(':')[0]),
+                    '-b',
+                    str(self.port.split(':')[1]),
+                    '--crc',
+                    '-o',
+                    captureFileLocation,
+                ]
+                self.is_active = True
+                ModuleHelper.WriteIntoDebugLogger('OT_Sniffer: [cmd] --> %s' % str(cmd))
+                self.subprocess = subprocess.Popen(cmd)
+
+        except Exception as e:
+            ModuleHelper.WriteIntoDebugLogger('OT_Sniffer: [startSniffer] --> Error: ' + str(e))
+
+    def stopSniffer(self):
+        """
+        Method for ending the sniffer capture.
+        Should stop background capturing, No further file I/O in capture file.
+        """
+        if self.is_active:
+            self.is_active = False
+            if self.subprocess:
+                self.subprocess.terminate()
+                self.subprocess.wait()
+
+    def setChannel(self, channelToCapture):
+        """
+        Method for changing sniffer capture
+        @param channelToCapture : int :
+            channel number is passed to change the channel which is set during the constructor call.
+        """
+        self.channel = channelToCapture
+
+    def getChannel(self):
+        """
+        Method to query sniffer for the channel it is sniffing on
+        @return : int : current capture channel of this sniffer instance.
+        """
+        return self.channel
+
+    def validateFirmwareVersion(self, addressofDevice):
+        """
+        Method to query sniffer firmware version details.
+        Shall be used while discoverSniffer() to validate the sniffer firmware.
+        @param addressofDevice : string :
+            serial com port or IP address,shall be None if need to verify own fireware version.
+        @return : bool : True if expected firmware is found , False if not
+        """
+        return True
+
+    def isSnifferCapturing(self):
+        """
+        method that will return true when sniffer device is capturing
+        @return : bool
+        """
+        return self.is_active
+
+    def getSnifferAddress(self):
+        """
+        Method to retrun the current sniffer's COM/IP address
+        @return : string
+        """
+        return self.port
+
+    def globalReset(self):
+        """Method to reset all the global and class varibaled"""
+        pass
diff --git a/tools/harness-sniffer/README.md b/tools/harness-sniffer/README.md
new file mode 100644
index 000000000..9206e6d8e
--- /dev/null
+++ b/tools/harness-sniffer/README.md
@@ -0,0 +1,17 @@
+OpenThread Sniffer Integration with Thread Test Harness
+=============================
+After following the steps below, you will be able to run Test Harness with OpenThread sniffer.
+1) require python3 is installed on windows and in the system environment path.
+2) require TestHarness is updated on `ReportEngine.pyd`
+
+## Setup
+1. install pyspinel (for python3 only)
+    ```
+    git clone https://github.com/openthread/pyspinel.git
+    cd <path-to-pyspinel>
+    python setup.py install
+    ```
+2. Copy "OT_Sniffer.py" to `C:\GRL\Thread1.1\Thread_Harness\Sniffer`.
+
+
+