Some analysts expect second quarter earnings for big banks will be disappointing because trading revenue has fallen and consumers and businesses have resisted taking out new loans, hurting bank profitability. 

"It's going to be a very lackluster quarter with numbers that aren't going to impress anybody," said Brad Hintz, an analyst at Sanford Bernstein. "We're in a wait and see environment for all the financials right now."

J.P. Morgan Chase and Citigroup announce their second quarter earnings this week. Goldman Sachs and Bank of America, whose stock prices are each down 20 percent since the beginning of the year, announce next week.

Trading volumes are down because investors fled to safety in U.S. treasury bonds as the crisis in Greece was unfolding, Hintz said.

And because of the slow economy, the demand for new loans is low, which means banks are sitting on a lot of cash that's not earning much interest.

To boost profitability, Hintz, a former chief financial officer at the now-defunct Lehman Brothers, said banks won't be shy to cut costs — and that means layoffs.

"Whether you love it or hate it, I think the one fact that we all know is that Wall Street shoots their wounded and eats their young, which means they will cut expenses in order to get their returns up," he said.

Hintz expects some Wall Street firms will cut high-paying and thus high-cost managing directors, particularly in fixed income departments, later this month and August.