Stifel Financial Corp.’s global wealth management business provided a positive boost to the company’s first quarter results, the firm said Monday, as its institutional group business’s revenue dipped from the fourth quarter.

Stifel’s global wealth management business posted $238.4 million in net revenue for the first quarter, up from $199.4 million from the same period one year ago. Those results were due to larger commission revenue with increased client assets and productivity, as well as growth in asset management and service fees and equity underwriting sales credits, the firm said. Global wealth management revenue was a slight increase from its $236.4 million for the fourth quarter.

Those results come as Stifel reported $366.6 million in overall net revenue for the first quarter, up 18% from the fourth quarter of 2010. The firm’s net income for the first quarter was $31.4 million, or $.50 per share. Stifel had $1.5 million in after-tax expenses during the quarter related to its acquisition of investment bank Thomas Weisel Partners Group that began last year.

“I’m pleased with the contributions from our global wealth management segment,” Stifel Chairman, President and Chief Executive Ronald J. Kruszewski said in the firm’s earnings call. “As we look forward, I continue to see that as a continued driver of our growth and profitability.”

The global wealth management business had pre-tax operating income of $61.5 million for the first quarter, versus $62.7 million for the fourth quarter and $39.2 million for the first quarter of 2010.

Within that division, the private client group’s net revenue rose 21% compared to the first quarter of 2010 to $229.5 million, which was also a 1% increase from the fourth quarter. Stifel Bank’s net revenue decreased 9% from the first quarter of 2010 to $8.9 million.

By contrast, Stifel’s institutional group, which includes its investment banking business, saw its net revenue fall to $127 million from $165.9 million in the fourth quarter. Net revenue for that business was $113.3 million in the first quarter of 2010. Stifel’s institutional business had pre-tax operating income of $21.4 million for the quarter, down from $43.7 million for the fourth quarter and $27.5 million from a year earlier.

“Consistent with industry trends, our investment banking results in the quarter were sequentially lower, primarily impacted by a decline in advisory and municipal underwriting activity, particularly when compared with our record fourth quarter revenues,” Kruszewski said in the earnings release. “Our pipeline remains promising, with a significant weighting in the technology sector.”