The Scottish company saw its profits fall from £521m in the first half of 2017 to £478m in the same period this year.
Nearly a year after the merger between Standard Life and Aberdeen Asset Management, it has continued to register outflows, with investors pulling out £16.6bn so far in 2018.
Standard Life Aberdeen's assets under management now stand at £610bn, compared to £627bn this time last year.
In a statement, Martin Gilbert and Keith Skeoch, joint chief executives of Standard Life Aberdeen, said: "Conditions for the asset management industry continue to be challenging.
"However, our gross inflows remain robust and are spread across a diverse range of investment capabilities, and our market-leading adviser platforms continue to grow.
"Our investment and distribution teams are winning new mandates and we have a good and diverse pipeline of business from around the world."
We recognise that a turnaround in performance of these products may take some time and will depend partly on market conditions.The statement added: "We are actively taking steps to improve our investment performance in key areas and are encouraged by the impact of these initiatives."
Earlier this year Standard Life Aberdeen's biggest client Scottish Widows withdrew £109bn of assets from the company.
At the time Scottish Widows chief executive Antonio Lorenzo said the merger of Standard Life and Aberdeen has resulted in his company's assets being managed by a "material competitor".
Since then Standard Life Aberdeen announced it would sell its insurance arm to Phoenix Group in a £3.2bn deal and the chief executives said this deal would complete the company's "transformation" into a capital-light business.
The company now expects there to be savings of £350m of savings as a result of the merger.
As part of the Phoenix deal, Standard Life Aberdeen has held onto what the statement to markets called its "valuable and fast growing" UK platforms, Wrap and Elevate, as well as its financial planning business, 1825.
Combined, the two platforms saw net inflows of £3.1bn, with assets under administration growing from £58bn to £61bn.
In total, the company's retail division, which includes the two platforms and the advice business, saw net inflows of £2.5bn, down from £3.7bn last year.
The company's asset management division, Aberdeen Standard Investments, saw net outflows of £13.6bn, up from £9bn last year.
A sizeable part of this was accounted for by outflows from the Global Absolute Return Strategies fund (Gars), which investors withdrew £5.3bn from.
The fund has underperformed its benchmark - the IA Targeted Absolute Return sector - over one year, three years and five years and has fallen to £17.5bn in size.
The Standard Life Aberdeen statement said: "While net outflows remain a challenge in a tough market, they are concentrated in a narrow range of strategies and we remain focused on supporting our teams and improving performance in Gars, emerging markets and global equities, while remaining true to our investment style.
"However, we recognise that a turnaround in performance of these products may take some time and will depend partly on market conditions."
damian.fantato@ft.com
