diff --git a/lib/sb3_definitions.json b/lib/sb3_definitions.json
index 008e9c5a..1f5f9a0d 100644
--- a/lib/sb3_definitions.json
+++ b/lib/sb3_definitions.json
@@ -220,6 +220,9 @@
                 "opcode": {
                     "type": "string"
                 },
+                "comment": {
+                    "type": "string"
+                },
                 "inputs": {
                     "type": "object",
                     "additionalProperties": {
@@ -281,6 +284,24 @@
                 "opcode"
             ]
         },
+        "comment": {
+            "type": "object",
+            "properties": {
+                "blockId": {"$ref": "#/definitions/optionalString"},
+                "text": {
+                    "type": "string",
+                    "maxLength": 8000
+                },
+                "minimized": {"type": "boolean"},
+                "x": {"type": "number"},
+                "y": {"type": "number"},
+                "width": {"type": "number"},
+                "height": {"type": "number"}
+            },
+            "required": [
+                "text"
+            ]
+        },
         "stage": {
             "type": "object",
             "description": "Description of property (and/or property/value pairs) that are unique to the stage.",
@@ -378,6 +399,10 @@
                     "type": "object",
                     "additionalProperties": {"$ref":"#/definitions/broadcast_message"}
                 },
+                "comments": {
+                    "type": "object",
+                    "additionalProperties": {"$ref": "#/definitions/comment"}
+                },
                 "costumes": {
                     "type": "array",
                     "items": {"$ref":"#/definitions/costume"},
diff --git a/test/fixtures/data.js b/test/fixtures/data.js
index 05095483..81b2f08d 100644
--- a/test/fixtures/data.js
+++ b/test/fixtures/data.js
@@ -5,6 +5,7 @@ var path = require('path');
 // Build file listings
 var sb = glob.sync(path.resolve(__dirname, './data/*.sb'));
 var sb2 = glob.sync(path.resolve(__dirname, './data/*.sb2'));
+var sb3 = glob.sync(path.resolve(__dirname, './data/*.sb3'));
 var sprite2 = glob.sync(path.resolve(__dirname, './data/*.sprite2'));
 // Sprite2 and Sprite3 jsons have modified file extensions
 // so that they don't get caught here but can still be used by the
@@ -15,9 +16,10 @@ var gzipJson = glob.sync(path.resolve(__dirname, './data/*.json.gz'));
 // Read files and convert to buffers
 for (var a in sb) sb[a] = fs.readFileSync(sb[a]);
 for (var b in sb2) sb2[b] = fs.readFileSync(sb2[b]);
-for (var c in json) json[c] = fs.readFileSync(json[c]);
-for (var d in gzipJson) gzipJson[d] = fs.readFileSync(gzipJson[d]);
-for (var e in sprite2) sprite2[e] = fs.readFileSync(sprite2[e]);
+for (var c in sb3) sb3[c] = fs.readFileSync(sb3[c]);
+for (var d in json) json[d] = fs.readFileSync(json[d]);
+for (var e in gzipJson) gzipJson[e] = fs.readFileSync(gzipJson[e]);
+for (var f in sprite2) sprite2[f] = fs.readFileSync(sprite2[f]);
 
 // Return listings
 module.exports = {
@@ -40,8 +42,13 @@ module.exports = {
         example_sprite2_json: fs.readFileSync(path.resolve(__dirname, './data/_example_sprite.sprite2json')),
         bananas_sprite2: fs.readFileSync(path.resolve(__dirname, './data/_bananas.sprite2'))
     },
+    sb3_comments: {
+        comments: fs.readFileSync(path.resolve(__dirname, './data/_comments.sb3')),
+        invalid_comments: fs.readFileSync(path.resolve(__dirname, './data/_invalid_comments.sb3'))
+    },
     sb: sb,
     sb2: sb2,
+    sb3: sb3,
     json: json,
     gzipJson: gzipJson,
     sprite2: sprite2
diff --git a/test/fixtures/data/_comments.sb3 b/test/fixtures/data/_comments.sb3
new file mode 100644
index 00000000..ce937c45
Binary files /dev/null and b/test/fixtures/data/_comments.sb3 differ
diff --git a/test/fixtures/data/_invalid_comments.sb3 b/test/fixtures/data/_invalid_comments.sb3
new file mode 100644
index 00000000..39d9714c
Binary files /dev/null and b/test/fixtures/data/_invalid_comments.sb3 differ
diff --git a/test/integration/comments_sb3.js b/test/integration/comments_sb3.js
new file mode 100644
index 00000000..57bacff6
--- /dev/null
+++ b/test/integration/comments_sb3.js
@@ -0,0 +1,44 @@
+var test = require('tap').test;
+var JSZip = require('jszip');
+var data = require('../fixtures/data');
+var parser = require('../../index');
+
+test('comments sb3', function (t) {
+    parser(data.sb3_comments.comments, false, function (err, result) {
+        t.equal(err, null);
+        t.equal(Array.isArray(result), true);
+        var res = result[0];
+        var possibleZip = result[1];
+        t.type(res, 'object');
+        t.equal(res.projectVersion, 3);
+        t.equal(possibleZip instanceof JSZip, true);
+
+        t.type(res.targets[0].comments, 'object');
+        t.equal(Object.values(res.targets[0].comments).length, 1);
+
+        t.type(res.targets[1].comments, 'object');
+        t.equal(Object.values(res.targets[1].comments).length, 6);
+
+        t.end();
+    });
+});
+
+test('invalid comments sb3', function (t) {
+    parser(data.sb3_comments.invalid_comments, false, function (err, result) {
+        t.type(err, 'object');
+        t.type(err.validationError, 'string');
+
+        var sb3Errors = err.sb3Errors;
+        t.type(sb3Errors, 'object');
+        t.type(sb3Errors[0].keyword, 'string');
+        t.type(sb3Errors[0].dataPath, 'string');
+        t.match(sb3Errors[0].dataPath, /^\.targets\[1\]\.comments\[.*\]\.width$/);
+        t.type(sb3Errors[0].schemaPath, 'string');
+        t.type(sb3Errors[0].message, 'string');
+        t.equal(sb3Errors[0].message, 'should be number');
+        t.type(sb3Errors[0].params, 'object');
+        t.type(result, 'undefined');
+
+        t.end();
+    });
+});