diff --git a/lib/doc/ja/Additional.lyx b/lib/doc/ja/Additional.lyx
index d9d403fe47..48f7faee83 100644
--- a/lib/doc/ja/Additional.lyx
+++ b/lib/doc/ja/Additional.lyx
@@ -125,7 +125,7 @@ End
 \fontencoding auto
 \font_roman "lmodern" "IPAexMincho"
 \font_sans "default" "IPAexGothic"
-\font_typewriter "default" "default"
+\font_typewriter "default" "IPAGothic"
 \font_math "auto" "auto"
 \font_default_family default
 \use_non_tex_fonts false
diff --git a/lib/doc/ja/Customization.lyx b/lib/doc/ja/Customization.lyx
index 4341ff1b11..629857c195 100644
--- a/lib/doc/ja/Customization.lyx
+++ b/lib/doc/ja/Customization.lyx
@@ -91,7 +91,7 @@ End
 \fontencoding auto
 \font_roman "lmodern" "IPAexMincho"
 \font_sans "default" "IPAexGothic"
-\font_typewriter "default" "default"
+\font_typewriter "default" "IPAGothic"
 \font_math "auto" "auto"
 \font_default_family default
 \use_non_tex_fonts false
diff --git a/lib/doc/ja/Math.lyx b/lib/doc/ja/Math.lyx
index d4bfdee710..d8f2f09500 100644
--- a/lib/doc/ja/Math.lyx
+++ b/lib/doc/ja/Math.lyx
@@ -188,7 +188,7 @@ End
 \fontencoding auto
 \font_roman "lmodern" "IPAexMincho"
 \font_sans "default" "IPAexGothic"
-\font_typewriter "default" "default"
+\font_typewriter "default" "IPAGothic"
 \font_math "auto" "auto"
 \font_default_family default
 \use_non_tex_fonts false
diff --git a/lib/doc/ja/UserGuide.lyx b/lib/doc/ja/UserGuide.lyx
index abf9366bce..9b79a3e6cc 100644
--- a/lib/doc/ja/UserGuide.lyx
+++ b/lib/doc/ja/UserGuide.lyx
@@ -100,7 +100,7 @@ End
 \fontencoding auto
 \font_roman "lmodern" "IPAexMincho"
 \font_sans "default" "IPAexGothic"
-\font_typewriter "default" "default"
+\font_typewriter "default" "IPAGothic"
 \font_math "auto" "auto"
 \font_default_family default
 \use_non_tex_fonts false