Police are alarmed by figures that show there are more assaults on Australia Day than any other public holiday.

There were 121 non-family violence related assaults on January 26 last year – almost double the number seen on an average day in Victoria.

The worst regions for assault are the Melbourne, Mornington Peninsula and Frankston police service areas, which cover similar boundaries to local councils.

There were an average of nine non-family violence assaults in Melbourne over the past five years, followed by an average of 6.8 in Mornington and 5.8 in Frankston.

Deputy Commissioner Tim Cartwright said the worrying trend was probably fuelled by warmer weather, alcohol, drugs and people celebrating the day in large groups.