diff --git a/src/blkmaker/BlkMakerMain.cc b/src/blkmaker/BlkMakerMain.cc
index 81606af07..5c34338b2 100644
--- a/src/blkmaker/BlkMakerMain.cc
+++ b/src/blkmaker/BlkMakerMain.cc
@@ -38,6 +38,7 @@
 #include "Utils.h"
 
 #include "bitcoin/BlockMakerBitcoin.h"
+#include "eth/EthConsensus.h"
 #include "eth/BlockMakerEth.h"
 #include "bytom/BlockMakerBytom.h"
 #include "sia/BlockMakerSia.h"
@@ -99,6 +100,16 @@ shared_ptr<BlockMakerDefinition> createDefinition(const Setting &setting)
   shared_ptr<BlockMakerDefinition> def;
 
   readFromSetting(setting, "chain_type",  chainType);
+
+  // The hard fork Constantinople of Ethereum mainnet has been delayed.
+  // So set a default height that won't arrive (9999999).
+  // The user can change the height in the configuration file
+  // after the fork height is determined.
+  if (chainType == "ETH") {
+    int constantinopleHeight = 9999999;
+    setting.lookupValue("constantinople_height", constantinopleHeight);
+    EthConsensus::setHardForkConstantinopleHeight(constantinopleHeight);
+  }
   
 #if defined(CHAIN_TYPE_STR)
   if (CHAIN_TYPE_STR == chainType)
diff --git a/src/blkmaker/blkmaker.cfg b/src/blkmaker/blkmaker.cfg
index 0f99f0ec9..5b9cb3585 100644
--- a/src/blkmaker/blkmaker.cfg
+++ b/src/blkmaker/blkmaker.cfg
@@ -45,6 +45,12 @@ blk_makers = (
     );
     #solved share topic
     solved_share_topic = "EthSolvedShare";
+
+    # The hard fork Constantinople of Ethereum mainnet has been delayed.
+    # So set a default height that won't arrive (9999999).
+    # The user can change the height in the configuration file
+    # after the fork height is determined.
+    constantinople_height = 9999999;
   },
   {
     chain_type = "SIA"; //blockchain short name
diff --git a/src/eth/EthConsensus.cc b/src/eth/EthConsensus.cc
index 84de48ecb..fd4d68293 100644
--- a/src/eth/EthConsensus.cc
+++ b/src/eth/EthConsensus.cc
@@ -24,7 +24,18 @@
 #include "EthConsensus.h"
 
 #include <algorithm>
+#include <glog/logging.h>
 
+// The hard fork Constantinople of Ethereum mainnet has been delayed.
+// So set a default height that won't arrive (9999999).
+// The user can change the height in the configuration file
+// after the fork height is determined.
+int EthConsensus::kHardForkConstantinopleHeight_ = 9999999;
+
+void EthConsensus::setHardForkConstantinopleHeight(int height) {
+    kHardForkConstantinopleHeight_ = height;
+    LOG(INFO) << "Height of Ethereum Constantinople Hard Fork: " << kHardForkConstantinopleHeight_;
+}
 
 EthConsensus::Chain EthConsensus::getChain(std::string chainStr) {
     // toupper
@@ -95,7 +106,7 @@ int64_t EthConsensus::getStaticBlockRewardClassic(int nHeight) {
 // static block rewards of Ethereum Main Network
 int64_t EthConsensus::getStaticBlockRewardFoundation(int nHeight) {
  // Constantinople fork at block 7080000 on Mainnet.
-  if (nHeight >= 7080000) {
+  if (nHeight >= kHardForkConstantinopleHeight_) {
     return 2e+18;
   }
   // Ethereum Main Network has a static block reward (3 Ether) before height 7080000.
diff --git a/src/eth/EthConsensus.h b/src/eth/EthConsensus.h
index 0bf148047..5f295c7b9 100644
--- a/src/eth/EthConsensus.h
+++ b/src/eth/EthConsensus.h
@@ -54,6 +54,8 @@ class EthConsensus {
     // the 0.875 will be returned.
     static double getUncleBlockRewardRatio(int nHeight, Chain chain);
 
+    static void setHardForkConstantinopleHeight(int height);
+
 protected:
     // static block rewards of Ethereum Classic Main Network
     static int64_t getStaticBlockRewardClassic(int nHeight);
@@ -62,6 +64,12 @@ class EthConsensus {
 
     static double getUncleBlockRewardRatioClassic(int nHeight);
     static double getUncleBlockRewardRatioFoundation(int nHeight);
+
+    // The hard fork Constantinople of Ethereum mainnet has been delayed.
+    // So set a default height that won't arrive (9999999).
+    // The user can change the height in the configuration file
+    // after the fork height is determined.
+    static int kHardForkConstantinopleHeight_;
 };
 
 #endif // ETH_CONSENSUS_H_
diff --git a/src/slparser/ShareLogParserMain.cc b/src/slparser/ShareLogParserMain.cc
index 4487d41e7..99d60a0c5 100644
--- a/src/slparser/ShareLogParserMain.cc
+++ b/src/slparser/ShareLogParserMain.cc
@@ -43,6 +43,7 @@
 #include "bitcoin/StatisticsBitcoin.h"
 #include "bitcoin/ShareLogParserBitcoin.h"
 
+#include "eth/EthConsensus.h"
 #include "eth/StatisticsEth.h"
 #include "eth/ShareLogParserEth.h"
 
@@ -254,6 +255,16 @@ int main(int argc, char **argv) {
     // Track duplicate shares within N blocks.
     int32_t dupShareTrackingHeight = 3;
     cfg.lookupValue("dup_share_checker.tracking_height_number", dupShareTrackingHeight);
+    
+    // The hard fork Constantinople of Ethereum mainnet has been delayed.
+    // So set a default height that won't arrive (9999999).
+    // The user can change the height in the configuration file
+    // after the fork height is determined.
+    if (chainType == "ETH") {
+      int constantinopleHeight = 9999999;
+      cfg.lookupValue("sharelog.constantinople_height", constantinopleHeight);
+      EthConsensus::setHardForkConstantinopleHeight(constantinopleHeight);
+    }
 
     //////////////////////////////////////////////////////////////////////////////
     //  dump shares to stdout
diff --git a/src/slparser/slparser.cfg b/src/slparser/slparser.cfg
index 8beb85084..b8f6ee70b 100644
--- a/src/slparser/slparser.cfg
+++ b/src/slparser/slparser.cfg
@@ -21,6 +21,12 @@ slparserhttpd = {
 sharelog = {
   chain_type = "ETH";
   data_dir = "/work/btcpool/data/sharelog";
+
+  # The hard fork Constantinople of Ethereum mainnet has been delayed.
+  # So set a default height that won't arrive (9999999).
+  # The user can change the height in the configuration file
+  # after the fork height is determined.
+  constantinople_height = 9999999;
 };
 
 # Used to detect duplicate share attacks on ETH mining.