The Federal Council, the country's highest executive authority, said it had “decided to support the public health sector by mobilising up to 2,500 troops as backup.”
It said authorities would consider requests from individual cantons as the virus' second wave hits the country hard.
The army will notably assist hospitals in administering basic care and testing as Switzerland looks to ramp up capacity with some hospitals in worst-affected regions seeing intensive care facilities approaching saturation point.
The government said troops also may be deployed to assist with transport of infected people.
Authorities in the French-speaking Fribourg canton had Friday called for military assistance saying they could no longer cope with the skyrocketing number of cases.
Relative to neighbouring countries, Switzerland avoided the worst of the first wave but has seen 10,000 fresh cases and 72 deaths since Tuesday while the proportion of positive tests rose to one in four.
The country of 8.56 million has a death toll of some 2,500 to date for some 200,000 declared cases.
Virginie Masserey, head of vaccination strategies at the Swiss Federal Office of Public Health, warned intensive care facilities could reach saturation point as early as Sunday.
During the first wave, the army had helped deliver millions of sanitary masks to shops.