You Do Need power plug adapter while traveling from Australia to San Marino.

Here is Why You Need An Adapter

The outlet and plug type used in San Marino are C, F and L and in Australia is I. This is how they look like.

Australia

In Australia, outlets of type I are in use.

Type I

San Marino

In San Marino, outlets of type C, F and L are in use.

Type C

Type F

Type L