Schultz, who will become executive chairman in April 2017, said he would focus on building ultra-premium Reserve stores and showcase Roastery and Tasting Rooms around the world as well as setting the brand's "social impact agenda" that includes sending employees to college and recruiting veterans.
Starbucks had signalled the change in July, but its shares fell 3.6 percent to $56.41 in extended trading on Thursday, as investors recalled the company's decline after Schultz handed over the reins in 2000. He returned in 2008.
"Having him step down as CEO raised the anxiety level," said Stephens analyst Will Slabaugh, who said that Schultz is the heart and soul of the brand, its entrepreneurial leader and its saviour.
"We're in a much better position on every level," said Schultz, who returned for his second stint as CEO in the depths of the "Great Recession," when Starbucks' stock was trading below $10. Late last year, it hit an all-time high above $60. Schultz has put Starbucks in the national spotlight, asking customers not to bring guns into stores and urging conversations on race relations.
Many of the campaigns have generated controversy, but analysts have not seen a hit to financial results and the efforts have raised the profile of the coffee company and cemented Schultz's status as a national figure.
"The idea that he's replaceable, I think that's erroneous," said Bill Smead, CEO of Smead Capital Management in Seattle, which owns Starbucks shares. He compared the change to the retirement of long-time McDonald's Corp
The announcement on Thursday also came as investors worry about the restaurant industry's stubborn traffic declines. Starbucks has held up better than most, but it has not been immune.
Johnson is a former technology executive who became president and chief operating officer at Starbucks in March 2015.
Johnson has been on the Starbucks board since 2009 but most of his career was in the technology industry. He was the chief executive of Juniper Networks Inc
On a conference call after the announcement, analysts pressed the company on timing and whether, with Schultz stepping aside, senior management still had the "merchant gene."
"Not having retail experience could be a problem over time," said Howard Penney, an analyst at Hedgeye Risk Management.
"I'm not leaving the company and I'm here every day," said Schultz, whose office is connected to Johnson's.
Traffic at established Starbucks cafes fell in the last quarter, which Johnson has attributed to a change in the company's loyalty programme, and Starbucks forecast a mid-single-digit rise in 2017 same-store sales.
The company dismissed speculation that Schultz could be preparing for a new career in politics.
"He has no plans to run for political office, as he has said many times, and will remain with the company as Starbucks executive chairman, focusing on premium coffee," a spokeswoman said.