Drivers who kill someone in the most serious cases of dangerous and careless driving will now face life sentences.
Causing death by dangerous driving, or death by careless driving while drunk or on drugs, will carry the top-level punishment.
Jail terms in cases involving mobile phones, speeding or street racing will now be the equivalent of manslaughter, the Ministry of Justice said.
Road safety charity Brake said it was a "major victory" for victims' families.
It follows criticism that sentences for those convicted over road deaths were too lenient.
The increase will apply to offences in England, Scotland and Wales, but not Northern Ireland, which has separate road safety laws.
Barrister Matthew Scott told BBC Radio 5 live the change would not increase road safety.
Announcing the change, justice minister Dominic Raab said: "Based on the seriousness of the worst cases, the anguish of the victims' families, and maximum penalties for other serious offences such as manslaughter, we intend to introduce life sentences of imprisonment for those who wreck lives by driving dangerously, drunk or high on drugs."
A new offence of causing serious injury through careless driving is also to be created.
(Published by BBC - October 15, 2017)