In a statement, health officials say the deaths can be linked "directly or indirectly" to the heat. The number far surpasses previous estimates.
It was the government's first official death toll estimate. One of the few organizations to issue an estimate, France's emergency hospital physicians' association, had earlier this week said the death toll was at least 100.
Health Minister Jean-Francois Mattei said the blistering heat wave has caused a "veritable epidemic" of death in France.
The news came temperatures began abating Wednesday, but even before the health ministry's announcement, health authorities faced renewed accusations that people died unnecessarily from the heat wave.
Paris awoke to a temperature of 73 degrees, noticeably cooler than the record early morning heat of 77.9 registered at the start of the week.
Britain also felt the relief of cooler weather Wednesday following record temperatures.
It was warm in London and southeastern England, with temperatures ranging from 77 to 82. But that was a refreshing change compared to Sunday, when the nation recorded its hottest day ever — 100.58 degrees at Gravesend, in southern England.
Temperatures remained high in Switzerland on Wednesday, with forecasters saying the Swiss would have to wait another day before the thermometer starts to drop. The temperature in the capital, Bern, reached 98.6, the hottest day since 1865.
It remained in the high 90s across Germany on Wednesday, with a record high temperature overnight of 81.7, measured in Neutstadt, in southern Germany.
Forecasters are predicting a drop in temperatures by the weekend, with winds bringing cooling air in some regions. Despite thunderstorms and showers forecast in the north, officials say there is still no end to the dry spell that has made forests susceptible to fires.
Wednesday was so far the warmest day in Austria this year, with temperatures of almost 102. The Vienna meteorological institute said temperatures will ease Friday.
The temperature in the Romanian capital, Bucharest, reached 90 on Wednesday, but was expected to drop Sunday, with hail storms and cool weather to come.
Meteo France forecaster Michel Daloz said the thermometer climbed toward 90 in Paris by early Wednesday afternoon, down from nearly 104-degree heat Tuesday.
The fortified city of Carcassone in the south roasted in 106-degree heat, while the Rhone Valley registered 102, Daloz said. The heat has prompted winemakers in some areas to begin harvesting their grapes early.
The high heat continued across Italy on Wednesday. Meteorologists said some relieving thundershowers could come to northeast Italy, including parts of the Alps, on Thursday or Friday.
On Wednesday, days after the French government was first accused of a slow response to heat-related deaths, Prime Minister Jean-Pierre Raffarin asked the Paris region to launch an emergency hospital plan to handle a massive influx of patients.
At the height of the heat wave, Paris and other regions baked in temperatures sometimes topping 104 — agonizing in a country where air conditioning is not widespread.
The surgeon general's office said Paris region mortuaries were full because of "the increase in deaths due to the heat wave."
"In the majority of cases, these were not inevitable natural deaths, but missed chances, that's to say lives that should have been saved in a modern health system," Francois Aubart, head of a Paris region medical trade union, said in an interview with the daily Le Parisien.
"What shocks me is that state representatives did not react after the first deaths were announced."
But Health Minister Jean-Francois Mattei said that "contrary to what is said, the hospitals are performing well."
"In extreme situations like this extreme heat, there's a surge of activity that is sometimes hard to deal with," he said.
The government insists extra beds were put aside to treat victims of heat-related illnesses, and the Defense Ministry said military hospitals took patients from overburdened Paris hospitals.
In Spain, 42 deaths have been blamed on the weather. The nation's hottest spots on Wednesday were in the south and southwest, with temperatures hitting 107.6 in Seville and Caceres.
Morgues and funeral directors have reported skyrocketing demand for their services since the heat wave took hold. General Funeral Services, France's largest undertaker, said it handled some 3,230 deaths from Aug. 4-10, compared to 2,300 on an average week in the year — a 37 percent jump.
Many people died in their apartments. One police officers' union in Paris called on the government to deploy the army to help retrieve bodies.
The ministry said its estimate was partly drawn from studying deaths in 23 Paris region hospitals from July 25-Aug. 12 and from information provided by General Funeral Services.
Mattei acknowledged "difficulties" for the government in managing the surge in temperatures, but said that hospital staffers were performing in an "exemplary" manner in response.
The government "carried out the responses that were needed" as soon as the first cases of heat-related death appeared about a week ago, Mattei said.
"We didn't just remain inactive," he said.
Paris City Hall said Wednesday it had taken extra measures to ensure that city-run funeral homes would remain open to bury bodies on Friday, a holiday in France, and recall more than 30 municipal workers from vacation.
To protect the elderly, the city's 13 retirement homes bought extra fans and atomizers to keep their residents cool in a country where air conditioning is not widespread.
According to the U.S. Centers For Disease Control and Prevention, over the past 20 years heat killed more Americans than hurricanes, lightning, tornadoes, floods, and earthquakes combined.
National Oceanic and Atmospheric Administration records indicate that in the heat wave of 1980, 1,250 Americans died.