Demand for its drinks in Europe weakened, and a strong dollar ate into revenue from other markets outside the US, including Latin America.
The company reported a 4% decline in profits to $1.89bn in the first quarter from $1.98bn in 2015.
However, global sales volumes rose 2% in the first quarter.
Its performance was helped by brands including Fanta and strength in still drinks such as bottled water and sports drinks.
But the world's biggest drinks maker said that sales volume for drinks like Diet Coke and Cherry Coke declined in North America, Europe and the Middle East and Africa.
"Our operating results are driven by our commitment to sustainable growth, and we are confident that we have the right strategies in place to achieve our full-year outlook and drive long-term value for our system and shareowners," said chief executive officer Muhtar Kent.
Coke's sales in Europe, its third biggest market, declined 1% in the quarter ended 1 April, while Latin America sales plunged 12.2%.
Sales in Asia Pacific, including China, dropped 4%, but volumes increased after the company sharply cut prices.
In Asia, pricing is expected to be a "little volatile and bumpy" in the coming quarters chief operating officer James Quincey said.
Coke is banking on new marketing initiatives, such as the "One Brand" programme rolled out on Wednesday, to boost sales.
All cans and bottles of Coca-Cola branded drinks will have a similar appearance, prominently featuring the red colour associated with regular Coke, but with a band of the colour for brands Diet Coke, Coke Zero and Coke Life.
Shares in fizzy drinks giant Coca-Cola have fallen more than 4% after the firm reported a fall in profits.