The couple bought the spinach at a Giant food store. Sri Sindhusha Boddapati, of Chevy Chase, tells news outlets that she was making lunch on Monday when she noticed something crawling inside the bag.
She said she initially thought it was a cricket, but realized it was a scorpion after capturing it in a water bottle.
Her husband, Shanmukha Pranay Rajeev Jerripothula, took the bottle to the Landover store where they bought the spinach. He said he asked store officials to stop selling the spinach, but they refused.
In a statement, Giant Food of Landover, Maryland, described what happened as an "isolated incident." The company says it is taking steps to ensure it doesn't happen again.
The Associated Press contributed to this report.