The IGP-M index, which encompasses wholesale, construction costs and consumer prices, posted no changes from April, compared with a 0.15 percent gain in April, the private think tank Fundação Getulio Vargas said on Wednesday. Wholesale prices fell 0.30 percent from April, while consumer prices rose 0.33 percent.
The index had been expected to rise 0.04 percent, according to the median forecast of 17 economists polled by Reuters.
A steep rise in food prices earlier this year helped push consumer inflation above the ceiling of the central bank's target, prompting policymakers to lift interest rates off record lows. The central bank led by Alexandre Tombini is expected to raise the benchmark Selic rate for a second straight time later on Wednesday.
In the 12 months through May, the IGP-M index rose 6.22 percent, down from 7.30 percent in the previous month.