Kenya scaled up distribution of the nets in 2004, when only seven percent of the population had access to this anti-mosquito screen. Last year, the figure was 67 percent.
Greg Fegan of the KEMRI-Wellcome Trust Research Programme in Kilifi, Kenya, led a team to investigate the success of the initiative.
They examined 3,500 children once a year over three years, in four rural districts -- Bondo, Kwale, Makueni and Kisii.
Exactly 100 children died during the key first two years of the study. But the death rate among children who did not have a recently-treated bednet was 44 percent higher compared to those with the net.
The findings, published in the peer-reviewed Lancet, confirm figures issued by the Kenyan government in August.
The UN's World Health Organisation (WHO) is calling for the distribution of free treated nets as low-cost weapon against malaria.
The disease affects more than a billion people worldwide and kills a million -- mainly under age five -- every year, the vast majority in sub-Saharan Africa.