Tokyo, Japan (BBN)-Asian shares opened mixed as investors remained cautious ahead of US growth data and the outcome of the Federal Reserve meeting on Wednesday.
The central bank is set to wrap up its two-day policy meeting later in the day and give an indication on whether it is still on track to raise interest rates, reports BBC.
Trading volume was also thinner with the region's biggest market - Japan- closed for a public holiday.
Australia's benchmark S&P/ASX 200 was down 1.1% to 5,884.9 in early trade.
Investors are awaiting earnings reports from major supermarket retailers Woolworths and Wesfarmers' Coles.
Chinese shares headed lower with Hong Kong's Hang Seng index down 0.3% to 28,358.8, while the Shanghai Composite was down 1.5% to 4,409.42.
Meanwhile, South Korea's benchmark Kospi index was up 0.1% to 2,149.22.
Shares of Samsung Electronics were up 1.5% after its earnings came in line with the guidance it released earlier this month.
The tech giant reported a first-quarter operating profit of 6 trillion won ($5.64bn; £3.63bn).