diff --git a/HISTORY-ID.txt b/HISTORY-ID.txt
index 3c5af94f..6adecb8a 100644
--- a/HISTORY-ID.txt
+++ b/HISTORY-ID.txt
@@ -294,3 +294,5 @@
     - Commonized IDD_ADDDLGINIT and IDD_MODIFYDLGINIT.
     - Changed the design of RES_str_get and RES_str_set.
     - Added RES_get_text and RES_set_text functions to EGA.
+- v.5.7.8 (2023-XX-YY)
+    - Improved Portuguese (Brazilian) translation.
diff --git a/HISTORY-ITA.txt b/HISTORY-ITA.txt
index 74866311..e6884655 100644
--- a/HISTORY-ITA.txt
+++ b/HISTORY-ITA.txt
@@ -294,3 +294,5 @@
     - Commonized IDD_ADDDLGINIT and IDD_MODIFYDLGINIT.
     - Changed the design of RES_str_get and RES_str_set.
     - Added RES_get_text and RES_set_text functions to EGA.
+- v.5.7.8 (2023-XX-YY)
+    - Improved Portuguese (Brazilian) translation.
diff --git a/HISTORY-JPN.txt b/HISTORY-JPN.txt
index d8f9cdf9..fca11862 100644
--- a/HISTORY-JPN.txt
+++ b/HISTORY-JPN.txt
@@ -638,3 +638,5 @@
     - IDD_ADDDLGINIT と IDD_MODIFYDLGINIT を共通化。
     - RES_str_get と RES_str_set の設計を変更。
     - RES_get_text と RES_set_text 関数をEGAに追加。
+- v.5.7.8 (2023-XX-YY)
+    - ポルトガル語（ブラジル）の翻訳を改良。
diff --git a/HISTORY-KOR.txt b/HISTORY-KOR.txt
index 782ddcc5..483c1ab1 100644
--- a/HISTORY-KOR.txt
+++ b/HISTORY-KOR.txt
@@ -295,3 +295,5 @@
     - 공통화된 IDD_ADDLGINIT 및 IDD_MODIFYDLGINIT.
     - RES_str_get 및 RES_str_set의 설계를 변경했습니다.
     - EGA에 RES_get_text 및 RES_set_text 함수를 추가했습니다.
+- v.5.7.8 (2023-XX-YY)
+    - Improved Portuguese (Brazilian) translation.
diff --git a/HISTORY-PTB.txt b/HISTORY-PTB.txt
index 8b847975..3910f936 100644
--- a/HISTORY-PTB.txt
+++ b/HISTORY-PTB.txt
@@ -293,4 +293,6 @@
 - v.5.7.7 (2023-06-05)
     - Comunizado IDD_ADDDLGINIT e IDD_MODIFYDLGINIT.
     - Alterou o design de RES_str_get e RES_str_set.
-    - Adicionou as funções RES_get_text e RES_set_text ao EGA.
\ No newline at end of file
+    - Adicionou as funções RES_get_text e RES_set_text ao EGA.
+- v.5.7.8 (2023-XX-YY)
+    - Improved Portuguese (Brazilian) translation.
diff --git a/HISTORY.txt b/HISTORY.txt
index 2e47b592..27809b58 100644
--- a/HISTORY.txt
+++ b/HISTORY.txt
@@ -294,3 +294,5 @@
     - Commonized IDD_ADDDLGINIT and IDD_MODIFYDLGINIT.
     - Changed the design of RES_str_get and RES_str_set.
     - Added RES_get_text and RES_set_text functions to EGA.
+- v.5.7.8 (2023-XX-YY)
+    - Improved Portuguese (Brazilian) translation.
diff --git a/installer.iss b/installer.iss
index f4edf7a9..e288c0d2 100644
--- a/installer.iss
+++ b/installer.iss
@@ -87,12 +87,14 @@ Source: "README-ITA.txt"; DestDir: "{app}"; Flags: ignoreversion
 Source: "README-JPN.txt"; DestDir: "{app}"; Flags: ignoreversion
 Source: "README-KOR.txt"; DestDir: "{app}"; Flags: ignoreversion
 Source: "README-TR.txt"; DestDir: "{app}"; Flags: ignoreversion
+Source: "README-PTB.txt"; DestDir: "{app}"; Flags: ignoreversion
 Source: "LICENSE.txt"; DestDir: "{app}"; Flags: ignoreversion
 Source: "HISTORY.txt"; DestDir: "{app}"; Flags: ignoreversion
 Source: "HISTORY-ID.txt"; DestDir: "{app}"; Flags: ignoreversion
 Source: "HISTORY-ITA.txt"; DestDir: "{app}"; Flags: ignoreversion
 Source: "HISTORY-JPN.txt"; DestDir: "{app}"; Flags: ignoreversion
 Source: "HISTORY-KOR.txt"; DestDir: "{app}"; Flags: ignoreversion
+Source: "HISTORY-PTB.txt"; DestDir: "{app}"; Flags: ignoreversion
 Source: "Standardize.md"; DestDir: "{app}"; Flags: ignoreversion
 Source: "HYOJUNKA.txt"; DestDir: "{app}"; Flags: ignoreversion
 Source: "TRANSLATORS.txt"; DestDir: "{app}"; Flags: ignoreversion
diff --git a/src/RisohEditor.cpp b/src/RisohEditor.cpp
index 720d2351..c658dbd9 100644
--- a/src/RisohEditor.cpp
+++ b/src/RisohEditor.cpp
@@ -11873,6 +11873,12 @@ void MMainWnd::OnCommand(HWND hwnd, int id, HWND hwndCtl, UINT codeNotify)
     case ID_OPENHISTORYID:
         OnOpenLocalFile(hwnd, L"HISTORY-ID.txt");
         break;
+    case ID_OPENREADMEPTB:
+        OnOpenLocalFile(hwnd, L"README-PTB.txt");
+        break;
+    case ID_OPENHISTORYPTB:
+        OnOpenLocalFile(hwnd, L"HISTORY-PTB.txt");
+        break;
     default:
         bUpdateStatus = FALSE;
         break;
diff --git a/src/lang/pt_BR.rc b/src/lang/pt_BR.rc
index 4fcf5ee8..3b2aca19 100644
--- a/src/lang/pt_BR.rc
+++ b/src/lang/pt_BR.rc
@@ -134,7 +134,9 @@ IDR_MAINMENU MENU
     POPUP "A&juda"
     {
         MENUITEM "Abrir &README.txt (Inglês)", ID_OPENREADME
+        MENUITEM "Abrir README-&PTB.txt", ID_OPENREADMEPTB
         MENUITEM "Abrir &HISTORY.txt", ID_OPENHISTORY
+        MENUITEM "Abrir HISTORY-P&TB.txt", ID_OPENHISTORYPTB
         MENUITEM "Abrir &LICENSE.txt", ID_OPENLICENSE
         MENUITEM SEPARATOR
         MENUITEM "&Guia do RisohEditor", ID_GUIDE
diff --git a/src/resource.h b/src/resource.h
index e8d28916..cf837b51 100644
--- a/src/resource.h
+++ b/src/resource.h
@@ -520,6 +520,8 @@
 #define ID_OPENREADMETR                     274
 #define ID_OPENREADMEID                     275
 #define ID_OPENHISTORYID                    276
+#define ID_OPENREADMEPTB                    277
+#define ID_OPENHISTORYPTB                   278
 
 #define MSGID_HELLO                         101
 #define MSGID_SAMPLE                        102