Rakon says the volatile and very strong New Zealand dollar is hurting its profitability.
The technology company, which makes components for global positioning systems and mobile phones, says the high kiwi has cost it $20 million in the current financial year.
Shares in Rakon fell 7 cents to 79 cents on Wednesday.
Managing director Brent Robinson says that if the currency stays at high levels, Rakon's earnings before tax for the March 2012 year will be between $14 million-$18 million.
That's still more than the $12 million it collected in earnings before tax for the 2011 year.
But Mr Robinson says the company would be earning more if the dollar was lower.
He says Rakon's underlying global business is performing well, but is significantly affected by the exchange rates with the US dollar and British pound.
The New Zealand dollar has been trading at an all time high against both of these currencies.
Mr Robinson says Rakon has foreign exchange protection in place to minimise any further negative affect on the current year's results, should the New Zealand dollar continue to rise.
Rakon will update investors on the dollar's affect on its business at its annual meeting of shareholders on 9 September.