Nine people were swept away in the avalanche, which struck an off-piste slope, according to Emmanuel Dubost of the local police. Two helicopters are at the site, along with police and mountain rescue teams, Mr Dubost said.
Rescuers pulled out one survivor who was buried in snow and is described as being in critical condition.
The number of dead is expected to rise.
Two people have so far been pulled out alive and three remain unaccounted for, rescue services said.
The 400-metre wide avalanche occurred at an altitude of 2,100 metres (6,900 feet), in an off-piste section of the ski area at Tignes, a popular resort near the Italian border.
Police and emergency services were rushed to Tignes from the nearby resort of Courchevel to reinforce those already at the scene.
The identities and nationalities of those killed have not been announced.
Tignes Avalanche: At least four killed skiing off-piste at popular French Alps resort
13 February 2017
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At least four people have been killed in an avalanche in the ski resort of Tignes, in the French Alps.
