The bank, in its latest outlook released Tuesday from its headquarters in Manila, also cited China's slowing growth for lowering its 2013 growth forecast to 6.3 percent from its April forecast of 6.6 percent. The forecast for next year was lowered to 6.4 percent from April's 6.7 percent.
"Continued tepid demand from the major industrial economies, coupled with slower growth in (China), are weighing on the outlook for developing Asia," the ADB said on its website.
China is likely to see its economy expand 7.7 percent this year and 7.5 percent in 2014 after a growth of 7.8 percent last year, the bank said. It said import and export growth have slowed given the weak external demand.
The bank's chief economist Changyong Rhee said the "knock-on effect" of China's slower pace is definitely a concern for the region. He said the there is also more subdued activity across much of developing Asia.
India's growth is likely to be 5.8 percent this year, down from 6 percent earlier forecast, due to slow progress in pushing through reforms needed to ease business bottlenecks. The bank did not change its earlier forecast of 6 percent for next year.
The report also trimmed forecasts for Central Asia, reflecting the sluggish economic performance of Kazakhstan and Georgia, and for the Pacific.
"Inflation pressures, meanwhile, are waning on the back of declining energy and food prices, given slower global demand for fuels and bumper grain harvests," the bank said.