The money, which is meant to keep food production going and to treat people under threat, will be distributed through the UN organization's UNICEF, the UN's refugee agency, and the Food and Agricultural Organization.
The area is expected to experience an extra-long dry period this year.
"We have signs of severe malnourishment in children," says Åsa Palmgren, at Sida's West African department, to Swedish Radio. "If we don't do anything now, we're going to see a famine later. So now we are simply making a major investment."
Countries facing problems include Burkina Faso, Mauritania, Mali, Niger, Senegal, Chad and northern parts of Cameroon and Nigeria. Around 15.6 million people have an unstable food supply. Nearly a million children are at risk of severe malnourishment.
Political and ethnic worries have worsened the problem. The European Union decided in March to increase its food support and send experts to the region to train security forces.