McDonald's has been too obsessed with fast-casual dining restaurants like Chipotle Mexican Grill and Panera Bread and needs to refocus if it wants to recover from its slump, a former executive with the fast food giant told CNBC on Wednesday.
"Focus on the business you're in versus focusing on the business you're not in. I think that obsession has gotten them off track and will continue to get them off track," said Larry Light, former chief marketing officer of McDonald's.
Earlier this week, the company reported global same-store sales shrank 1.8 percent in January, worse than analysts were expecting. Last month, it warned business would be weak in the first half of 2015. McDonald's also said it is cutting its annual construction budget to the lowest in more than five years as it opens fewer restaurants in struggling markets.
All this comes after a tumultuous year, one of the toughest in decades for the chain. McDonald's is now trying to stage a recovery, simplifying its menu and replacing its CEO.
Light, who penned an op-ed on the subject in The Wall Street Journal on Wednesday, told "Squawk on the Street" McDonald's complex menu is a big part of its problem and should be the company's first priority.
"The menu exploded because they were so obsessed with everything outside their category. They kept on adding to the menu without subtracting form the menu," said Light, now CEO of brand management consulting firm Arcature.
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That goes against what the company did when it worked on a turnaround during Light's tenure, and the rule was for every item added to the menu, another is taken off, he noted.
While McDonald's is beginning to address the issue, Light said he doesn't think it is being aggressive enough.
As for the change in CEOs, Light said it is a signal that the board wants action. However, he pointed out that outgoing CEO Don Thompson inherited a mess.
"Most of the seeds of destruction happened" under prior management, Light said.
Read More McDonald's CEO Don Thompson steps aside
He also called McDonald's current "Pay With Lovin'" campaign "silly."
McDonald's will allow winners of its "Pay With Lovin' Instant Win Game" to pay for their food with a random act of "Lovin'" between Feb. 2 and 14.
"I doubt it is going to sell hamburgers and fries," Light said. "What they need now ... is a message that will dramatically capture the interest of their core costumers and bring them back to McDonald's."
—Reuters contributed to this report.