A Perth financial adviser is on trial accused of stealing more than $1 million from the superannuation accounts of eight clients and spending it on online gambling.

Mark Raymond Sebo, 41, has pleaded not guilty to 36 charges of stealing the money over a 10-day period in July and August 2019.

WA's District Court was told the eight clients had hired Mr Sebo to help with their self-managed superannuation funds and he was only allowed to access their accounts with their authorisation.

However, state prosecutor Paul Usher said over the 10 days, funds had been transferred to Mr Sebo's business and personal accounts without the express permission of the clients.

Mr Usher said evidence would be presented to the court that showed most of the money had been used to gamble on three online betting sites.

Mr Sebo encouraged clients to complain

Some of the clients had contacted Mr Sebo when they noticed the transactions and the court heard he had replied with text messages urging them to make a complaint to the Australian Securities and investments commission (ASIC).

In one text message, he is alleged to have said "this is my error ... I can no longer fix it for anyone as my accounts have been frozen."

"The best you can do at the moment is make a complaint to ASIC."

The court heard most of the money had not been recovered.

Mr Sebo is representing himself at the trial and he denies any wrongdoing.