The Swedish swimming star hit the tile in the time of 23.50 and won the competition in the money-tight International Swimming League in Naples.
She was twelve hundredths ahead of Polish Katarzyna Wasick and another thirteen hundredths ahead of Siobhan Haughey of Hong Kong.
The previous world year best in the distance was 24.15, set by the Dutchwoman Kira Toussaint in July.
Sarah Sjöström won Olympic silver in 50 freestyle in Tokyo earlier in August.