Chinese equities fell sharply on Tuesday, setting the negative trend across the region.
The mainland's Shanghai Composite index dropped 6.2% to 3,748.16, on worries over the strength of the economy.
China's central bank set the yuan's midpoint near Monday's closing price. But the currency edged down a further 0.2% raising fresh concerns that it could fall further.
Hong Kong's Hang Seng index closed 1.4% lower at 23,474.97.
In Japan, the region's biggest market, the Nikkei 225 index closed down 0.3% at 20,554.47, after giving up gains it had made earlier in the day.
The benchmark index in South Korea, the Kospi, closed down 0.6% at 1,956.26.
In Australia, investors were digesting a number of company results. Port and rail operator Asciano saw its shares rally 7% on strong earnings expectations and a buyout offer led by Canada's Brookfield Infrastructure Partners.
Fortescue Metals was the other top performer, with its shares rising 8% on news that the iron miner was contemplating the sale of some of its assets.
However, the market overall followed the region's trend into negative territory, with the benchmark S&P/ASX 200 ending the day 0.9% lower at 5,320.50.
Share prices in Thailand fell sharply as investors reacted to the deadly bomb blast in Bangkok, which the Thai government described as an attempt to destroy the economy.
The benchmark SET index of Thai stocks closed down 36.13 points, or 2.56%, at 1,372.61.
Shares from tourism-related firms were the hardest hit, with hoteliers such as Erawan Group, Minor International and Central Plaza down more than 10%.
A bomb explosion on Monday evening killed at least 20 people, including eight foreigners, at a Hindu shrine in a part of the Thai capital popular with tourists.
The Thai currency, the baht, also weakened. It shed as much as 0.5%, falling to its lowest against the US dollar in six years.
The baht has been sliding against the strengthening dollar over the past few years, with a particularly steep drop since April 2015.
However, Siddharth Mathur, a currency analyst at CitiFX, was wary of linking the drop to the Bangkok blast.
He told the BBC that "the fact that the Thai baht has hit another low does not mean that the impact from the unfortunate events of yesterday are significant".
"At the margin, of course this is terrible news - leisure tourist traffic to Bangkok may suffer for a brief period, and consumer/business sentiment in Bangkok may be hurt as well - but this by itself should not materially alter any other underlying economic trends."