There was a 1.1% drop in factory gate prices between June and July, according to new figures from the Central Statistics Office.
The data also show there was a monthly rise of 0.4% in July 2016, while annually in July there was a 1.9% drop in prices.
During July the price index for export sales decreased by 1.2%, while the index for home sales fell by 0.6%.
In the year to July there was a decrease of 2.4% in the price index for export sales and a rise of 1.4% in respect of the price index for home sales.
The CSO states that the most significant drops in July were for food products, mainly bread and confectionery (-2.3%), while computer, electronic and optical products saw a 1.5% fall.
Cars and trailers were 1.7% higher in price at the factory gate on a monthly basis, while dairy products also saw a jump (+1.4%).
