AmInvest comprises AmFunds Management and AmIslamic Funds Management.
With around 40 years of presence, the unit has approximately $10.7bn of total assets under management until the end of March this year.
A number of groups from other industrial sectors and private equity firms are among the contenders to buy AmInvest, the report said citing sources familiar with the matter.
It is expected that the deal, if finalised, could the fetch the company a valuation of $250m to $300m.
According to the sources, the discussions are now at a very nascent state and the deal could also fall through.
Responding to the Bloomberg report, an AMMB representative said that AmBank Group, part of AMMB, is currently not having any discussions regarding the sale of AmInvest with any other groups.
The company will reveal details if any as per the listing requirements, informed the official.
AmBank currently employs 9,000 people as well as provides services including wholesale banking, business banking, retail banking and others to more than three million individual and corporate clients.
If materialised, the deal could see AMMB joining a group of Southeast Asian banks that are disposing off their non-core assets.
In Thailand, Kasikornbank is reportedly weighing a sale of its asset management unit.
An exchange filing has disclosed that Malaysia’s Affin Bank secured the local regulator’s nod to get rid of its 63% stake in Affin-Hwang Asset Management.