According to GoEuro data, China's trains have the highest operating speed of any fleet worldwide, beating the "French TGV" and Japanese "SCMaglev". When it comes to the record books, the latter holds the world speed record at a blistering speed of 603km/h. The chart underneath shows the maximum operating speed and top speed record of trains (km/h) worldwide.
Following various fatal train crashes in last decade, the Chinese authorities had to cap their fleet of high-speed trains at a 300km/h. However some of the high-speed train were given exception to run at 350km/h, (nearly an hour off the journey time between Beijing and Shanghai). This triggered the introduction of an improved monitoring system that was designed to slow and stop the trains in the event of an emergency.
Source: GoEuro & Statista