Five million Somalis, or more than two out of five people in the country, do not have enough to eat, the United Nations said, calling for extra funds for food aid.
The latest figures represent an increase of 300,000 food insecure people since February, said the UN's humanitarian affairs office, OCHA.
"Humanitarian partners are ready to scale up response to help families struggling to find food to make it through the day," Peter De Clercq, Humanitarian Coordinator for Somalia, said in a statement.
He said a humanitarian response plan was only 32 per cent funded and additional resources were urgently needed to address malnutrition and access to food.
A study from the UN's food agency, FAO, said more than 1.1 million people cannot meet their daily food requirements while another 3.9 million Somalis require support.
Among the hungry are 300,000 children aged under five who are acutely malnourished, including more than 50,000 who are severely malnourished.
Harvests have been hit this year by a severe drought caused by the El Nino weather phenomenon which occurs every five to seven years.
Worst hit by hunger are the estimated 1.1 million people displaced from their homes by conflict, some of them forced to move several times during the past two decades.
Many of them live "in appalling conditions in settlements spread throughout the country," OCHA said.
"The simple truth is that today in Somalia, the weight of climate vulnerability, conflict and displacements is greater than the counterweight of people's resilience," Richard Trenchard, the FAO's Somalia officer, told a press conference.
In 2012, severe drought coupled with civil war caused a famine that left more than 250,000 people dead.