The Marine Accident Investigation Branch (MAIB) looked into recent fatalities and its findings were published late Wednesday.
Andrew Ashman, 49, from Kent, southeast England, suffered a fatal neck injury in September 2015 while on board a yacht after a preventer line broke and released the boom, which swung across the cockpit as the vessel performed two accidental turns through the wind or gybes.
His death was the first in the race's 20-year history.
Meanwhile Sarah Young, 40, from London, died when she was washed off the deck of the IchorCoal during the Pacific leg of the race in April last year.
She had not clipped on a tether that would have kept her attached to the yacht. When a wave broke over the deck she lost her footing before another wave washed her overboard. Young's body was recovered by her crew-mates and she was buried at sea.
The Marine Accident Investigation Branch (MAIB), a British government agency, looked into both fatalities and its findings were published late Wednesday.
Its report said the Clipper Race should alter its onboard manning policy and shore procedures so skippers are effectively supported and, if needed, questioned to make sure that the way in which their often inexperience crews sail remains as safe as possible.
Chief Inspector of Marine Accidents, Captain Steve Clinch, said: "The Clipper Round the World Race is an adventurous activity; operating with largely amateur and some novice crews, the yachts are often required to operate in some of the most hostile weather and sea conditions on earth.
"While acknowledging that Clipper Ventures plc has already done much to address the safety issues identified during the MAIB's investigations, I am nonetheless recommending that the company does even more to review and modify its yacht-manning policy and shore-based management procedures so that Clipper yacht skippers are effectively supported and, where appropriate, challenged to ensure safe working practices are always adhered to on board."
Clipper Race founder and chairman, Robin Knox-Johnston, one of Britain's most celebrated yachtsmen, responded to the MAIB report by saying: "These two fatalities, resulting from two very different incidents, were the first in our long history and are tragic, especially as they were caused primarily through momentary lapses in applying basic safety training.
"The report acknowledges that we have been proactive to mitigate the risks concerned even further," added Knox-Johnston, the first man to complete a single-handed non-stop circumnavigation of the globe by sea in 1969.
"Safety has been our highest priority since the Clipper Race was established in 1996, amassing huge experience through 10 biennial editions, 84 yacht circumnavigations (a cumulative four million nautical miles) with nearly 5000 crew undergoing extensive training.
"We frequently implement and develop safety procedures where there is no actual requirement, they are under constant review as a matter of course and we will continue to do so in light of the report's recommendations."