The benchmark Nikkei 225 index slid 0.35 percent or 71.86 points to 20,333.79 in early trade while the broader Topix index was down 0.35 percent or 5.14 points at 1,478.71.
Stocks are under pressure "on the backdrop of growing worries over the global economy amid intensifying US-China trade frictions," Mizuho Securities said in a note.
The dollar fetched 106.07 yen in early Asian trade, against 106.10 yen in New York and 105.91 yen in Tokyo on Thursday.
"There remains no end in sight" to US-China trade frictions, Tapas Strickland, senior analyst at National Australia Bank, said in a commentary.
"It is clear that China is willing to play the long game, meaning that to de-escalate tensions, any compromise will have to come from the US side," he said, citing an editorial from China's state-controled media The Global Times.
In Tokyo, China-linked exporters were among the losers, with industrial robot maker Fanuc trading down 1.21 percent at 17,845 yen and electronic parts maker Rohm off 1.44 percent at 7,510 yen.
Uniqlo casual wear operator Fast Retailing was down 0.89 percent at 61,880 after reports that some South Korean consumers were boycotting its products amid a tit-for-tat Tokyo-Seoul trade war linked to historical issues.