TOKYO (AP) _ Share prices finished mixed today on the Tokyo Stock Exchange, while the dollar rose against the Japanese yen.

The 225-issue Nikkei Stock Average finished at 16,780.98 points, down 1.90 points, or 0.01 percent, from Wednesday's close.

The Tokyo Stock Price Index of all issues listed on the first section, which shed 6.26 points Wednesday, added 6.38 points, or 0.49 percent, to finish at 1,298.25.

Trading volume on the market's first section totaled 200 million shares, up from Wednesday's 178.60 million. Advancing issues outnumbered declining issues 619 to 316, with 166 unchanged.

Prices moved sharply higher early in the session as reports late Wednesday that Crown Prince Naruhito would marry a Harvard-educated diplomat. Traders said the news temporarily eased pessimism over the nation's economic slowdown.

But the mood faded toward the end of the session, when index-linked selling slashed more than 200 points from the Nikkei index.

John Doyle, a futures trader with Maruso Securities, said the excitement over the potential economic benefits of an imperial wedding ''illustrates the real paucity of anything to go on in this market. ... There's no fundamental reason to buy.''

Nick Ainsworth of Morgan Stanley International said ''It's the wrong kind of market to be using this kind of issue as a pretext for buying stock.''

On the foreign exchange market, the dollar closed at 125.09 yen, up 0.25 yen from Wednesday's finish. After opening at 125.14 yen, it ranged from 125.05 yen to 125.17 yen.

Dealers said the dollar changed little as most players stood on the sidelines waiting for the outcome of a German central bank meeting today. Anticipation that Germany may cut interest rates, a move that would weaken the mark, kept investors out of the market.

They were also waiting for U.S. unemployment figures for December due out Friday, dealers said.

Spot trading totaled $2.59 billion, down from Wednesday's $2.89 billion.

The price of the benchmark No. 145 10-year Japanese government bonds closed at 106.79 points, up from Wednesday's 106.62-point finish. Their yield fell to 4.455 percent from 4.480 percent.