The group – which has not made a formal bid – could expect to pay around $300m (£194.5m) for the assets.
Henderson said in statement to the markets it was "discussions regarding a potential acquisition by the group of certain businesses of Ridgeworth Capital Management Inc."
The company stressed that the talks were at a very early stage with no formal bid on the table
Ridgeworth Capital oversees combined client assets of roughly $65bn (£42bn).
Henderson, which has assets under management of £58.1bn, is said to be interested in $36bn of Ridgeworth assets.
It is targeting institutional and retail fixed income and equity mandates.
Henderson shares were up 1.4p at 148p. The company has previously reported a dip in profits for 2009 as outflows countered the effect of recovering markets and positive investment performance.
The group, which last year took over struggling rival New Star, said recurring pre-tax profits after amortisation and charges was £63m, versus the £80.3m posted in 2008.
Favourable market and exchange rate movements added £5.1bn to Henderson’s assets last year, although this benefit was offset substantially by the loss of £4.2bn of assets withdrawn by Pearl Assurance
But chief executive Andrew Formica, 38, told City A.M. last week that he remained upbeat about the business.
The Australian said: “Business is going quite well for us. Investors have not waited for a sustained recovery period of typically around 12 to 18 months before getting back into the market…
“You need to buy on the dips. And if the market runs away from you don’t be too concerned, wait for it to come back.”