The news comes as the beauty products firm reports that sales fell 3% to £1.4 billion in the three months to end June.
Since joining the company in 2012, McCoy has launched a three-year transformation plan in 2016, executed the separation of Avon's North America business, and relocated the company's corporate headquarters to the UK. She has also appointed a new senior team.
McCoy said: "With the successful recruitment of a senior executive team with the skill and experience to implement the next phase of our strategy, the platform is in place for a new CEO to continue accelerating the pace of change and take Avon to sustainable profitable growth. I look forward to continuing to drive the Avon business forward and to working with our leadership team to ensure a smooth transition."
Avon's board has retained Heidrick & Struggles, an executive search firm with expertise in the consumer goods industry, to assist in identifying McCoy's successor.
Chan Galbato, non-executive chairman of Avon Products' board of directors, added: "Sheri has set Avon on a path to improved growth and profitability through the design and execution of the company's strategic plan and the recruitment of a team of executives to carry the plan to the next phase. We thank Sheri for her continued commitment to Avon as the company embarks on its next chapter."