diff -Naur a/boost/program_options/environment_iterator.hpp b/boost/program_options/environment_iterator.hpp
--- a/boost/program_options/environment_iterator.hpp	2004-05-14 15:40:30.000000000 +0200
+++ b/boost/program_options/environment_iterator.hpp	2014-01-17 17:33:52.710115300 +0100
@@ -12,6 +12,16 @@
 #include <string>
 #include <cassert>
 
+#if defined(_WIN32)
+#include <windows.h>
+#endif
+
+#if defined(_WIN32) && defined(__MINGW32__)
+#define ENVIRON_IT_TYPE LPTCH
+#else
+#define ENVIRON_IT_TYPE char**
+#endif
+
 namespace boost {
 
     class environment_iterator 
@@ -19,7 +29,7 @@
                               std::pair<std::string, std::string> >
     {
     public:
-        environment_iterator(char** environment)
+        environment_iterator(ENVIRON_IT_TYPE environment)
         : m_environment(environment)
         {
             get();
@@ -35,17 +45,28 @@
             if (*m_environment == 0)
                 found_eof();
             else {
+#if defined(_WIN32) && defined(__MINGW32__)
+                std::string s(m_environment);
+#else
                 std::string s(*m_environment);
+#endif
                 std::string::size_type n = s.find('=');
                 assert(n != s.npos);
                 value().first = s.substr(0, n);
                 value().second = s.substr(n+1);
-            }            
-            ++m_environment;
+#if defined(_WIN32) && defined(__MINGW32__)
+				m_environment += s.length() + 1;
+#else
+				++m_environment;
+#endif
+            }
         }
         
     private:
-        char** m_environment;
+        ENVIRON_IT_TYPE m_environment;
     };
 }
+
+#undef ENVIRON_IT_TYPE
+
 #endif
diff -Naur a/libs/program_options/src/parsers.cpp b/libs/program_options/src/parsers.cpp
--- a/libs/program_options/src/parsers.cpp	2012-04-08 12:02:26.000000000 +0200
+++ b/libs/program_options/src/parsers.cpp	2014-01-17 17:34:03.994197200 +0100
@@ -30,6 +30,7 @@
 
 #ifdef _WIN32
 #include <stdlib.h>
+#include <windows.h>
 #else
 #include <unistd.h>
 #endif
@@ -190,6 +191,10 @@
                       const function1<std::string, std::string>& name_mapper)
     {
         parsed_options result(&desc);
+
+#if defined(_WIN32) && defined(__MINGW32__)		
+		LPTCH environ = GetEnvironmentStrings();
+#endif
         
         for(environment_iterator i(environ), e; i != e; ++i) {
             string option_name = name_mapper(i->first);
@@ -201,6 +206,10 @@
                 result.options.push_back(n);
             }                
         }
+		
+#if defined(_WIN32) && defined(__MINGW32__)
+		FreeEnvironmentStrings(environ);
+#endif
 
         return result;
     }