The good times are not over yet for U.S. stocks, according to John Stoltzfus, chief investment strategist at Oppenheimer Asset Management. On Friday, Stoltzfus forecast the S&P 500 to reach 3,000 next year, making him the biggest bull on Wall Street.

"Going forward we expect many of the same thematics from 2017 to apply in the New Year as investors look to determine whether improving economic conditions and corporate fundamentals can boost stock markets higher for a third straight year," Stoltzfus said in a note to clients Friday. Some of those thematics include improving global economic conditions and rising corporate profits.

U.S. stocks have risen sharply in 2017, with the spiking nearly 18 percent to record highs.

Stoltzfus thinks this market still has more room to run, so long as the Federal Reserve's policy remains consistent.

"What it really needs to keep moving along is modest growth of inflation, modest wage growth, a Federal Reserve that remains very sensitive to the needs of the economy," Stolfuz said Friday on CNBC's "Fast Money."

"I would say the biggest risk would be if all of a sudden you've got a sense the Fed thought inflation was moving ahead of itself, and they had to increase the pace of the normalization," he added.

His 3,000 target on the broad index — the highest among major Wall Street strategists as of Friday morning — implies 13.8 percent upside from Thursday's close of 2,636.98.

To be sure, other major Wall Street strategists are also very bullish on stocks heading into 2018, but not as much as Stoltzfus. Morgan Stanley's Mike Wilson expects the S&P 500 to reach 2,750 over the next 12 months, while Deutsche Bank's Binky Chadha and Credit Suisse's Jonathan Golub have price targets on the index of 2,850 and 2,875, respectively.

Stoltzfus expects S&P 500 earnings to rise 13.5 percent to $146 per share, driving the gains in stocks.

"Improving fundamentals are likely to support higher stock prices and P/E multiple expansion next year," he said. "We remain constructive on further improvement for corporate fundamentals and see opportunity for growth in both the top and bottom-line. We expect forward guidance from corporate management teams to remain positive as global economies continue to improve at a sustainable rate of growth."

Corporate earnings have grown nicely this year, gaining at least 10 percent in the first two quarters of the year and advancing more than 6 percent in the third quarter.

Stoltzfus recommends investors buy tech stocks in 2018.

"While Info Tech has performed exceptionally well in 2017, we believe accelerating revenue and earnings growth in many segments supports such performance and augers well for the next year," he said.

Tech is by far the best-performing S&P 500 sector this year, having soared more than 35 percent.

Stoltzfus also has an outperform rating on consumer stocks, which "will continue to benefit from increased consumer confidence, improved employment and modest wage trends," industrials, health care and materials.

"In our opinion skeptic and bear capitulation appears to have just begun in the fourth quarter of 2017 and contributed to the number of this year's equity benchmark record highs. We believe that it is early in this process and multiples could expand further than we currently anticipate should the capitulation gain momentum," notes the strategist.

CNBC's Chloe Aiello contributed to this report.