diff --git a/lib/ini.js b/lib/ini.js
index beb390d..d2ec28c 100644
--- a/lib/ini.js
+++ b/lib/ini.js
@@ -108,8 +108,10 @@ const decode = (str, opt = {}) => {
   const out = Object.create(null)
   let p = out
   let section = null
-  //          section          |key      = value
-  const re = /^\[([^\]]*)\]\s*$|^([^=]+)(=(.*))?$/i
+  // A key may contain `=` as long as it is quoted, which is what encode()
+  // emits for such keys via safe().
+  //          section          |key                          = value
+  const re = /^\[([^\]]*)\]\s*$|^("(?:\\.|[^"\\])*"\s*|[^=]+)(=(.*))?$/i
   const lines = str.split(/[\r\n]+/g)
   const duplicates = {}
 
diff --git a/test/quoted-keys.js b/test/quoted-keys.js
new file mode 100644
index 0000000..f05d714
--- /dev/null
+++ b/test/quoted-keys.js
@@ -0,0 +1,34 @@
+const i = require('../')
+const test = require('tap').test
+
+test('decode a quoted key containing =', function (t) {
+  t.same(i.decode('"a=b"=c\n'), { 'a=b': 'c' })
+  t.same(i.decode('"key=with=eq"=v\n'), { 'key=with=eq': 'v' })
+  t.same(i.decode('"=lead"=v\n'), { '=lead': 'v' })
+  t.same(i.decode('"tr="=v\n'), { 'tr=': 'v' })
+  t.end()
+})
+
+test('encode then decode round-trips keys containing =', function (t) {
+  for (const obj of [
+    { 'a=b': 'c' },
+    { 'key=with=eq': 'v' },
+    { '=lead': 'v' },
+    { 'tr=': 'v' },
+    { a: { 'b=c': 'd' } },
+  ]) {
+    t.same(i.decode(i.encode(obj)), obj)
+  }
+  t.end()
+})
+
+test('an unquoted key still splits on the first =', function (t) {
+  t.same(i.decode('a=b=c\n'), { a: 'b=c' })
+  t.same(i.decode('a="x=y"\n'), { a: 'x=y' })
+  t.end()
+})
+
+test('a key with an unterminated quote is not treated as quoted', function (t) {
+  t.same(i.decode('"a=b\n'), { '"a': 'b' })
+  t.end()
+})