Telecom shares have risen 14 per cent in the past seven days. Last week, information technology-related shares closed at record highs.
NTT DoCoMo closed at Y2.94m (pounds 17,192), up 216 per cent this year. Softbank, one of the world's largest backers of internet businesses, gained Y1,100.
Investors said they expect to see strong demand for Nippon Telegraph & Telephone when Japan sells a fifth block of shares in the world's largest phone company this week.
Car manufacturers Mazda and other exporters may decline, however, limiting gains by the index, on concern that further gains by the yen may cut their overseas earnings in value when repatriated.
"I still see buying potential for information technology shares,'' said Takashi Otsubo, managing director at Fuji Investment Management's equity division, which handles Y108bn. "Fund managers managing new mutual funds seem to have bought only 50 per cent of what they need.''
Japanese government bonds, meanwhile, are expected to rise in the coming week on speculation the US Federal Reserve may not lift interest rates again this year, making domestic bonds attractive to investors.
The Washington Post reported last week that low inflation may allow the Fed to maintain a 5.25 per cent Federal Funds rate, which brought 30-year yields to their lowest levels in a month. The Fed has twice raised the rate since June.
"Bullish overseas bond market movements should be positive for bonds,'' said Xinyi Lu, chief strategist at Paribas Capital Markets.
The benchmark No 217, 10-year bond rose 0.385 last week, or Y192.5 per Y50,000 bond, to 100.299. The yield fell 4.5 basis points to 1.765 per cent. Ten-year bond futures for March delivery rose 1 to 131.85.
The Topix shares index of all issues on the Tokyo stock exchange's first section gained 32.96, or 2.1 per cent, to 1,596.85. The all-share index rose as high as 1,598.51 on Friday, its highest since October 1996.
The benchmark Nikkei 225 stock index gained 362.94, or 2.3 per cent, to 18,354.90 during the same period. Friday's close was the highest finish since 19 July.