diff --git a/src/Context.cc b/src/Context.cc
index e50e1b85..080c0c88 100644
--- a/src/Context.cc
+++ b/src/Context.cc
@@ -185,6 +185,7 @@ Context::Context(bool standalone,
     // when none of network interface has IPv4 address.
     setDefaultAIFlags(0);
   }
+  SocketCore::setIpDscp(op->getAsInt(PREF_DSCP));
   net::checkAddrconfig();
   // Bind interface
   if(!op->get(PREF_INTERFACE).empty()) {
diff --git a/src/OptionHandlerFactory.cc b/src/OptionHandlerFactory.cc
index 11f32620..a7ac5578 100644
--- a/src/OptionHandlerFactory.cc
+++ b/src/OptionHandlerFactory.cc
@@ -739,6 +739,15 @@ std::vector<OptionHandler*> OptionHandlerFactory::createOptionHandlers()
     op->addTag(TAG_ADVANCED);
     handlers.push_back(op);
   }
+  {
+    OptionHandler* op(new NumberOptionHandler
+                      (PREF_DSCP,
+                       TEXT_DSCP,
+                       "0",
+                       0));
+    op->addTag(TAG_ADVANCED);
+    handlers.push_back(op);
+  }
   {
     OptionHandler* op(new BooleanOptionHandler
                       (PREF_SELECT_LEAST_USED_HOST,
diff --git a/src/PeerInitiateConnectionCommand.cc b/src/PeerInitiateConnectionCommand.cc
index 384af239..4339d5de 100644
--- a/src/PeerInitiateConnectionCommand.cc
+++ b/src/PeerInitiateConnectionCommand.cc
@@ -83,6 +83,7 @@ bool PeerInitiateConnectionCommand::executeInternal() {
   createSocket();
   getSocket()->establishConnection(getPeer()->getIPAddress(),
                                    getPeer()->getPort(), false);
+  getSocket()->applyIpDscp();
   if(mseHandshakeEnabled_) {
     auto c = make_unique<InitiatorMSEHandshakeCommand>
       (getCuid(), requestGroup_, getPeer(),
diff --git a/src/PeerListenCommand.cc b/src/PeerListenCommand.cc
index 4c137e55..8bcd3f16 100644
--- a/src/PeerListenCommand.cc
+++ b/src/PeerListenCommand.cc
@@ -110,6 +110,7 @@ bool PeerListenCommand::execute() {
     std::shared_ptr<SocketCore> peerSocket;
     try {
       peerSocket = socket_->acceptConnection();
+      peerSocket->applyIpDscp();
       std::pair<std::string, uint16_t> peerInfo;
       peerSocket->getPeerInfo(peerInfo);
 
diff --git a/src/SocketCore.cc b/src/SocketCore.cc
index 74ebdb5c..fb78dc02 100644
--- a/src/SocketCore.cc
+++ b/src/SocketCore.cc
@@ -129,6 +129,7 @@ enum TlsState {
 } // namespace
 
 int SocketCore::protocolFamily_ = AF_UNSPEC;
+int SocketCore::ipDscp_ = 0;
 
 std::vector<std::pair<sockaddr_union, socklen_t> >
 SocketCore::bindAddrs_;
@@ -532,6 +533,11 @@ void SocketCore::setTcpNodelay(bool f)
   setSockOpt(IPPROTO_TCP, TCP_NODELAY, &val, sizeof(val));
 }
 
+void SocketCore::applyIpDscp()
+{
+  setSockOpt(IPPROTO_IP, IP_TOS, &ipDscp_, sizeof(ipDscp_));
+}
+
 void SocketCore::setNonBlockingMode()
 {
 #ifdef __MINGW32__
diff --git a/src/SocketCore.h b/src/SocketCore.h
index de7065d4..4442dc15 100644
--- a/src/SocketCore.h
+++ b/src/SocketCore.h
@@ -66,6 +66,7 @@ private:
   sock_t sockfd_;
 
   static int protocolFamily_;
+  static int ipDscp_;
 
   static std::vector<std::pair<sockaddr_union, socklen_t> > bindAddrs_;
 
@@ -120,6 +121,14 @@ public:
   // Enables TCP_NODELAY socket option if f == true.
   void setTcpNodelay(bool f);
 
+  // Set DSCP byte
+  void applyIpDscp();
+  static void setIpDscp(int ipDscp)
+  {
+    // Here we prepare DSCP value for IPTOS option, which sets whole DS field
+    ipDscp_ = ipDscp << 2;
+  }
+
   void create(int family, int protocol = 0);
 
   void bindWithFamily(uint16_t port, int family, int flags = AI_PASSIVE);
diff --git a/src/prefs.cc b/src/prefs.cc
index b22286ff..2ffc976c 100644
--- a/src/prefs.cc
+++ b/src/prefs.cc
@@ -361,6 +361,8 @@ PrefPtr PREF_SAVE_SESSION_INTERVAL = makePref("save-session-interval");
 PrefPtr PREF_ENABLE_COLOR = makePref("enable-color");
 // value: string
 PrefPtr PREF_RPC_SECRET = makePref("rpc-secret");
+// values: 1*digit
+PrefPtr PREF_DSCP = makePref("dscp");
 
 /**
  * FTP related preferences
diff --git a/src/prefs.h b/src/prefs.h
index 76be3ee2..592bad9a 100644
--- a/src/prefs.h
+++ b/src/prefs.h
@@ -298,6 +298,8 @@ extern PrefPtr PREF_SAVE_SESSION_INTERVAL;
 extern PrefPtr PREF_ENABLE_COLOR;
 // value: string
 extern PrefPtr PREF_RPC_SECRET;
+// values: 1*digit
+extern PrefPtr PREF_DSCP;
 
 /**
  * FTP related preferences
diff --git a/src/usage_text.h b/src/usage_text.h
index facba928..3f22e555 100644
--- a/src/usage_text.h
+++ b/src/usage_text.h
@@ -966,3 +966,13 @@
   _(" --enable-color[=true|false]  Enable color output for a terminal.")
 #define TEXT_RPC_SECRET                                                 \
   _(" --rpc-secret=TOKEN           Set RPC secret authorization token.")
+#define TEXT_DSCP                                                       \
+  _(" --dscp=DSCP                  Set DSCP value in outgoing IP packets of\n" \
+    "                              BitTorrent traffic for QoS. This parameter sets\n" \
+    "                              only DSCP bits in TOS field of IP packets,\n" \
+    "                              not the whole field. If you take values\n" \
+    "                              from /usr/include/netinet/ip.h divide them by 4\n" \
+    "                              (otherwise values would be incorrect, e.g. your CS1\n" \
+    "                              class would turn into CS4). If you are take commonly\n" \
+    "                              used values from RFC, network vendors' documentation,\n" \
+    "                              Wikipedia or any other source, use them as they are.")