diff --git a/lib/rollbar/notifier.rb b/lib/rollbar/notifier.rb
index fed66b40..e6b7d5b2 100644
--- a/lib/rollbar/notifier.rb
+++ b/lib/rollbar/notifier.rb
@@ -347,10 +347,10 @@ def extract_arguments(args)
           exception = arg
         elsif arg.is_a?(Hash)
           extra = arg
-          
+
           context = extra[:custom_data_method_context]
           extra.delete :custom_data_method_context
-          
+
           extra = nil if extra.empty?
         end
       end
@@ -411,7 +411,7 @@ def report(level, message, exception, extra, context)
     # If that fails, we'll fall back to a more static failsafe response.
     def report_internal_error(exception)
       log_error '[Rollbar] Reporting internal error encountered while sending data to Rollbar.'
-      
+
       configuration.execute_hook(:on_report_internal_error, exception)
 
       begin
@@ -517,12 +517,29 @@ def do_post(uri, body, access_token)
 
       request = Net::HTTP::Post.new(uri.request_uri)
 
-      request.body = body
+      request.body = pack_ruby260_bytes(body)
       request.add_field('X-Rollbar-Access-Token', access_token)
 
       handle_net_retries { http.request(request) }
     end
 
+    def pack_ruby260_bytes(body)
+      # Ruby 2.6.0 shipped with a bug affecting multi-byte body for Net::HTTP.
+      # Fix (committed one day after 2.6.0p0 shipped) is here:
+      # https://github.com/ruby/ruby/commit/1680a13a926b17661329beec1ded6b32aad16c1b#diff-00a99d8c71daaf5fc60a050da41f7261
+      #
+      # We work around this by repacking the body as single byte chars if needed.
+      if RUBY_VERSION == '2.6.0' && multibyte?(body)
+        body.unpack('C*').pack('C*')
+      else
+        body
+      end
+    end
+
+    def multibyte?(str)
+      str.chars.length != str.bytes.length
+    end
+
     def http_proxy_for_em(uri)
       proxy = http_proxy(uri)
       {
diff --git a/spec/rollbar_spec.rb b/spec/rollbar_spec.rb
index 76e0576f..043963db 100644
--- a/spec/rollbar_spec.rb
+++ b/spec/rollbar_spec.rb
@@ -159,6 +159,30 @@
         notifier.log('error', exception, extra_data, 'exception description')
       end
 
+      # See Notifier#pack_ruby260_bytes for more information.
+      context 'with multi-byte characters in the report' do
+        extra_data = { :key => "\u3042", :hash => { :inner_key => 'あああ' } }
+
+        it 'should send as multi-byte on ruby != 2.6.0',
+           :if => RUBY_VERSION >= '2.0.0' && RUBY_VERSION != '2.6.0' do
+          expect_any_instance_of(Net::HTTP::Post).to receive(:body=).with(
+            satisfy do |body|
+              body.chars.length < body.bytes.length && body.include?('あああ')
+            end
+          ).and_call_original
+          notifier.log('error', 'test message', extra_data)
+        end
+
+        it 'should unpack multi-byte and send as single byte on ruby == 2.6.0', :if => RUBY_VERSION == '2.6.0' do
+          expect_any_instance_of(Net::HTTP::Post).to receive(:body=).with(
+            satisfy do |body|
+              body.chars.length == body.bytes.length && body.force_encoding('utf-8').include?('あああ')
+            end
+          ).and_call_original
+          notifier.log('error', 'test message', extra_data)
+        end
+      end
+
       context 'with :on_error_response hook configured' do
         let!(:notifier) { Rollbar::Notifier.new }
         let(:configuration) do