Solicitor General Robert Buckland QC MP considered the sentences handed to ringleader Gerald McCann and four teenagers were unduly lenient and asked for a review.
The gang had committed a series of robberies against elderly victims, specifically targeting them because of their vulnerability and using force against them when they entered their homes.
Valuable items of jewellery and money were taken from the properties, including addresses in Batley and Gomersal, between May 1 and May 4 last year.
In one case, an 80-year old man was struck on the head with a metal coffee pot.
McCann, who was 22 at the time, was convicted of robbery and possession of a prohibited article at Leeds Crown Court last November.
He was jailed for eight years and four months, but the Court of Appeal has now agreed the sentence was too low and increased it to 10 years and four months.
The rest of the gang, who could not be identified due to their ages, were sentenced to time in a young offenders’ institute.
They have each had between 11 and 14 months added to their sentences, the shortest of which was originally four years.
Speaking after the hearing, the Solicitor General said: “This group of young men purposely set out to target vulnerable and elderly people. Many lives have been affected by their actions, and some of the victims no longer feel safe in their own homes.
"The Court’s decision to increase these sentences show that crimes of this nature will not be tolerated.”