"If Amazon and Disney can pay $15 an hour, so can McDonald's, which made $5.1 billion in profits last year," Sanders said on Twitter.
The tweet also was accompanied by a letter to Steve Easterbrook, the fast food chain's president and CEO, asking him to respect the constitutional rights of his workers to unionize.
Sanders said many McDonald's workers need assistance from the government's Supplemental Nutrition Assistance Program, which is commonly known as food stamps, Medicaid and public housing in order to survive.
"If McDonald's can afford to give its shareholders $7.7 billion, it can afford to pay all of its workers $15 an hour," Sanders wrote in the letter.
Last month, Sanders introduced legislation named the Bezos Act that would tax corporations for every dollar their low-wage workers receive in government health-care benefits or food stamps.
His criticism of McDonald's is not new. In 2015, he called for McDonald's to raise its minimum wage to $15 per hour, when the company announced they would pay $1 more than the required minimum wage. Sanders is now doubling down on his position, because of the recent wage hikes from other large companies.
"Our commitment to the communities we serve includes providing opportunities for restaurant employees to succeed at McDonald's and beyond with world-class training and education programs to help them build the skills needed for today's workforce," a McDonald's spokeswoman said when asked about Sanders' comments.
In an email, she called out employee benefits that go beyond the wages it pays to programs like tuition assistance to help employees earn college and high school diplomas. McDonald's has allocated $150 million over five years for such programs. However, the spokeswoman did not address wages specifically.
Sanders said he believes that if McDonald's raises the minimum wage, it would set an example for the entire fast food industry.
"In the year 2018, no one in America, especially those working for a profitable corporation like McDonald's, should be living in poverty," he wrote in the letter.