The SFO executed search warrants in cooperation with the Financial Markets Authority (FMA) at the offices of Barry Kloogh, a Dunedin-based financial adviser who is also the author of The Money Cookbook.
It not stated what the investigation is about but the FMA said it “is working to secure and preserve client funds”.
Local media reports said a team of officials had taken away a large number of boxes filled with material from Kloogh’s office.
The SFO said: “The action follows inquiries by the FMA, leading to a referral to the SFO.
“The FMA will be assessing any matters relating to the Financial Advisers Act and supporting the SFO investigation.”