The market awaited the 5 billion euro sale of February 2018 bonds, with analysts expecting the rise in the five-year Bund yield since the start of the year to help entice investors even though German debt still offers only meager returns.
German Bund futures were 4 ticks lower at 143.39 but analysts saw room for a rise after the contract posted its biggest weekly loss since September last week.
"There were oversold conditions for the Bund market and the market should again become more neutral. When it is oversold there is a tendency for the market to move slightly higher," said Piet Lammens, strategist at KBC, adding there was key resistance for the Bund first at 143.75 and then at 143.92.
"If we would move sustainably beyond these two levels the picture might become more bullish for the Bund."
At the German auction, investors would have to weigh low returns with the safety offered by Bunds against a fragile economic backdrop.
Auctions in Austria and the Netherlands on Tuesday showed there is still ample demand for higher-rated euro zone debt.
"I think that (the Bund sale) will go well. There seems to be a lot of central bank demand for the new five-year," one trader said.
Five-year German yields were little changed at 0.48 percent, up from 0.34 percent at the beginning of the year. Ten-year yields were flat at 1.50 percent.
"We seem to be holding the 1.50 level, which is obviously a key support level - (around) the upper end of recent trading range," Nick Stamenkovic, strategist at RIA Capital Markets said.
German Bunds opened lower as European shares were supported by Alcoa's results.
The largest aluminum producer in the United States said late on Tuesday it was optimistic demand for the metal would continue to grow in 2013, as it posted in-line profit and beat expectations on revenue.