Polk has been CEO since 2011 and a member of the board since 2009.
Newell, owner of brands like Rubbermaid, Sharpie, Calphalon and Graco baby products, has been struggling. In February, the company missed Wall Street's fourth-quarter sales expectations and Polk said at the time that Newell had been hurt by retailer bankruptcies, foreign exchange, inflation and tariffs. A year ago the stock was trading at $28.66.
"I have been privileged to lead Newell Brands for the past eight years. With the Accelerated Transformation Plan largely complete and the business beginning to turn, I believe now is the right time to transition to the next generation of leadership," Polk said in a statement.
Last April, Newell and hedge fund Starboard Value LP agreed to end a months-long proxy fight through a deal brokered by activist investor Carl Icahn that added three new independent directors to the board. Newell also agreed to accelerate its turnaround program by raising its asset sales target to about $10 billion from $6 billion.
The company said it retained the executive search firm Heidrick & Struggles to help look for the next CEO.