However the rail operator says revised services will still offer enough seats to meet current demand.
But there will be a reduction on services in the middle of the day, as off-peak customer journey numbers have fallen by almost 90 per cent year on year.
Reducing the number of trains in service is also said to allow additional cleaning to take place - of trains, in depots and at stations.
Following Scottish Government guidance that advises people against all non-essential travel, ScotRail says it has focused changes in areas of the country where people need it most.
It has provided earlier and later services for NHS workers at hospitals after consultation with health boards, and on services that are still being well used.
Phil Campbell, ScotRail Head of Customer Operations, said: “It’s vitally important that everyone stays at home unless there’s no other option, and we have made the latest changes to help those key workers get to where they need to be.
“Our own people are part of that key worker group, working on the frontline to help the country through this crisis and we continue to work with the Scottish Government to play our part to help.”