diff --git a/runtime/indent/nsis.vim b/runtime/indent/nsis.vim
new file mode 100644
index 0000000..223f4fa
--- /dev/null
+++ b/runtime/indent/nsis.vim
@@ -0,0 +1,91 @@
+" Vim indent file
+" Language:		NSIS script
+" Maintainer:		Ken Takata
+" URL:			https://github.com/k-takata/vim-nsis
+" Last Change:		2018-01-21
+" Filenames:		*.nsi
+" License:		VIM License
+
+if exists("b:did_indent")
+  finish
+endif
+let b:did_indent = 1
+
+setlocal nosmartindent
+setlocal noautoindent
+setlocal indentexpr=GetNsisIndent(v:lnum)
+setlocal indentkeys=!^F,o,O
+setlocal indentkeys+==~${Else,=~${EndIf,=~${EndUnless,=~${AndIf,=~${AndUnless,=~${OrIf,=~${OrUnless,=~${Case,=~${Default,=~${EndSelect,=~${EndSwith,=~${Loop,=~${Next,=~${MementoSectionEnd,=~FunctionEnd,=~SectionEnd,=~SectionGroupEnd,=~PageExEnd,0=~!macroend,0=~!if,0=~!else,0=~!endif
+
+if exists("*GetNsisIndent")
+  finish
+endif
+
+function! GetNsisIndent(lnum)
+  " If this line is explicitly joined: If the previous line was also joined,
+  " line it up with that one, otherwise add two 'shiftwidth'
+  if getline(a:lnum - 1) =~ '\\$'
+    if a:lnum > 1 && getline(a:lnum - 2) =~ '\\$'
+      return indent(a:lnum - 1)
+    endif
+    return indent(a:lnum - 1) + shiftwidth() * 2
+  endif
+
+  " Grab the current line, stripping comments.
+  let l:thisl = substitute(getline(a:lnum), '[;#].*$', '', '')
+  " Check if this line is a conditional preprocessor line.
+  let l:preproc = l:thisl =~? '^\s*!\%(if\|else\|endif\)'
+
+  " Grab the previous line, stripping comments.
+  " Skip preprocessor lines and continued lines.
+  let l:prevlnum = a:lnum
+  while 1
+    let l:prevlnum = prevnonblank(l:prevlnum - 1)
+    if l:prevlnum == 0
+      " top of file
+      return 0
+    endif
+    let l:prevl = substitute(getline(l:prevlnum), '[;#].*$', '', '')
+    let l:prevpreproc = l:prevl =~? '^\s*!\%(if\|else\|endif\)'
+    if l:preproc == l:prevpreproc && getline(l:prevlnum - 1) !~? '\\$'
+      break
+    endif
+  endwhile
+  let l:previ = indent(l:prevlnum)
+  let l:ind = l:previ
+
+  if l:preproc
+    " conditional preprocessor
+    if l:prevl =~? '^\s*!\%(if\%(\%(macro\)\?n\?def\)\?\|else\)\>'
+      let l:ind += shiftwidth()
+    endif
+    if l:thisl =~? '^\s*!\%(else\|endif\)\?\>'
+      let l:ind -= shiftwidth()
+    endif
+    return l:ind
+  endif
+
+  if l:prevl =~? '^\s*\%(\${\%(If\|IfNot\|Unless\|ElseIf\|ElseIfNot\|ElseUnless\|Else\|AndIf\|AndIfNot\|AndUnless\|OrIf\|OrIfNot\|OrUnless\|Select\|Case\|Case[2-5]\|CaseElse\|Default\|Switch\|Do\|DoWhile\|DoUntil\|For\|ForEach\|MementoSection\)}\|Function\>\|Section\>\|SectionGroup\|PageEx\>\|!macro\>\)'
+    " previous line opened a block
+    let l:ind += shiftwidth()
+  endif
+  if l:thisl =~? '^\s*\%(\${\%(ElseIf\|ElseIfNot\|ElseUnless\|Else\|EndIf\|EndUnless\|AndIf\|AndIfNot\|AndUnless\|OrIf\|OrIfNot\|OrUnless\|Loop\|LoopWhile\|LoopUntil\|Next\|MementoSectionEnd\)\>}\?\|FunctionEnd\>\|SectionEnd\>\|SectionGroupEnd\|PageExEnd\>\|!macroend\>\)'
+    " this line closed a block
+    let l:ind -= shiftwidth()
+  elseif l:thisl =~? '^\s*\${\%(Case\|Case[2-5]\|CaseElse\|Default\)\>}\?'
+    if l:prevl !~? '^\s*\${\%(Select\|Switch\)}'
+      let l:ind -= shiftwidth()
+    endif
+  elseif l:thisl =~? '^\s*\${\%(EndSelect\|EndSwitch\)\>}\?'
+    " this line closed a block
+    if l:prevl =~? '^\s*\${\%(Select\|Switch\)}'
+      let l:ind -= shiftwidth()
+    else
+      let l:ind -= shiftwidth() * 2
+    endif
+  endif
+
+  return l:ind
+endfunction
+
+" vim: ts=8 sw=2 sts=2