Japan's benchmark Nikkei index spent most of the day in negative territory to close down 0.19% at 18,264.22.
After surging almost 8% on Wednesday, the Tokyo index closed down 2.5% on Thursday  - among Asia's big losers.
Investor concern over whether or not the US Federal Reserve will raise interest rates next week has set in.
Investor sentiment has also been affected by the slowing Chinese economy, which is the world's second-biggest after the United States.
Japan's investors seem to shrug off news that Japan Post is seeking to raise as much as 1.39tn yen ($11.5bn, Â£7.4bn) in a stock market listing  - including its banking and insurance arms -  that would be one of the world's biggest this year.
The plan for the state-owned giant would be one of Japan's largest public share sales in more than 30 years.
Chinese shares traded mixed with the Shanghai Composite closing down 0.1% to 3,200.45, while Hong Kong's Hang Seng ended down 0.3% to 21,504.37.
Fresh measures from regulators to ease the volatility in the market may be working as both benchmark indexes did not move dramatically this week.
In Australia, the benchmark S&P/ASX 200 closed down 0.47% at 5,071.10 points despite gains on Wall Street overnight.
Analysts said investors there were also concerned about a possible rise in US interest rates.
After being the one bright spot in Asia yesterday, South Korea's benchmark Kospi closed down 1.06% at 1,941.37. The Bank of Korea left its benchmark rate unchanged at 1.5% on Friday.
Asia's markets were mostly down in trade on Friday following a rocky week featuring particularly volatile swings in Tokyo.