(New throughout, adds background, analyst comment)
By Anya George Tharakan and Deepa Seetharaman
Sept 3 (Reuters) - Amazon.com Inc's finance chief plans to step down next summer after more than a dozen years at the post, the e-commerce company said on Wednesday, at a time when more investors have been complaining about skimpy profits and high spending.
Chief Financial Officer Thomas Szkutak, 53, will retire in June 2015 and be succeeded by Brian Olsavsky, vice president of finance for global consumer business, Amazon said.
The transition comes at a delicate time for Amazon. The Seattle-based company last week announced its largest-ever deal to buy live-streaming gaming network Twitch Interactive for $970 million cash, beating out a rival bid from Google Inc.
The acquisition reflects how dramatically Amazon has expanded during Szkutak's tenure, from pure online retailer to one with many new business lines including original television shows, hardware and local services.
"Szkutak and Olsavsky will work together to conduct a seamless transition of CFO responsibilities over the next 10 months," Amazon said in a statement.
Amazon shares are down 15 percent so far this year, as some investors and analysts have worried about Chief Executive Jeff Bezos' decisions to spend big on new projects.
The company also faces heightened competition from Alibaba Group Holding Ltd, which handles more e-commerce than Amazon and eBay Inc combined in China and plans to make its market debut this month.
"Let's hope that the new guy talks slower and is willing to give us more information," Wedbush Securities analyst Michael Pachter said. He said he and other analysts have never spoken to Szkutak, who joined Amazon as CFO in October 2002.
Pachter said he did not expect big changes from Olsavsky, who has held many finance roles at Amazon since joining in April 2002, but hoped he would be willing to listen to feedback.
The announcement marks one of the highest-profile executive changeovers at Amazon. Since 2001, the year before Szkutak joined the company, Amazon's annual revenue has risen 23-fold.
Szkutak was hired from General Electric Co, where he held a variety of finance posts. He earned almost $9 million in the last three years as compensation, most of it in stock awards.
His next steps were not immediately clear. In a statement, he said he looked forward "to spending more time with my family and other outside interests." An Amazon spokesman said Szkutak was not available for an interview.
"Tom's impact over the past 12 years is evident in every part of our business," Bezos said in a statement. "Under Tom's stewardship, customers have benefited from category expansion and geographical expansion, along with amazing new businesses like AWS and Kindle." (Additional reporting by Abhirup Roy in Bangalore; Editing by David Gregorio)