Nokia reported a net profit of €915m (£563m to 31 March), compared with €1.05bn (£923m) a year ago.
The company posted a 12% decline in net sales to €7.01bn (£4.31bn), compared with €8.01bn (£4.93bn) for the first quarter of 2001.
The company suffered lower quarterly sales in Europe and the Americas, but that was partially offset by a growth in sales in the Asia-Pacific region, Nokia said.
The company said it believed it has maintained its estimated 37% share of the mobile phone market.
Nokia's network business posted a year-on-year decline of 29%, mainly because of the slower than expected pace of mobile phone operators in Europe and in China adding second-generation capacity to the networks.
For the second half of its financial year, Nokia believes the implementation of third-generation technology would have a positive impact of its networks business, the company said.
Nokia forecasted growth in its second-quarter sales of between 2% and 7% compared with the second quarter of last year.
For the entire mobile market, Nokia has set its yearly volume sales estimates for 2002 at between 400 million and 420 million units, compared with last year's estimated market volume of 380 million units. Nokia said it has lowered its market sales estimates in light of the weak market.
In terms of future growth, Nokia predicted that Multimedia Messaging Service (MMS) will be the primary revenue driver and, with that in mind, said that most of its mobile devices planned for release next year will be MMS-enabled.