Consumer inflation, excluding the impact of the April 2014 tax rise, returned to zero for the first time in nearly two years in February.
Meanwhile, household consumption was 2.9% lower than a year ago, while retail sales were down 1.8%.
The Nikkei closed down 1% at 19,285.63.
The dollar was flat at 119.18 yen on Friday, compared with its level in New York trade.
Lingering concerns over the conflict in Yemen limited market gains elsewhere.
Chinese shares were mixed with the Shanghai Composite closing up 0.3% at 3,691.10 - finishing the week up about 2%. Hong Kong's Hang Seng index ended down slightly at 24,486.2.
Data showing profits earned by Chinese industrial firms fell 4.2% in January-February from a year ago - were offset by expectations of fresh money inflows after China waived the $1bn limit on a foreign fund investment.
Australian shares ended higher with banks and consumer staple stocks posting the best gains.
The S&P/ASX 200 climbed 0.7% to 5,919.9 after recording its biggest fall in three and a half months on Thursday, when it dropped 1.6%.
Despite Friday's gains, the index ended the week down 0.9%.
South Korea's benchmark Kospi index closed down 0.1% to 2,019.8 points. meaning it was 0.9% lower over the week.
Asian markets experienced mixed fortunes after weak economic data from Japan underlined the struggle policymakers face in reviving the world's third-largest economy.