Around 50 countries, including Australia, signed up to take part in Hope for Creation. Participating churches devote a section of their services to climate change.
Organisers Tearfund said there was an "urgent" need for action on climate change and that the impact of erratic weather patterns was already having a "devastating" impact on impoverished communities and their livelihoods.
Ben Niblett, Tearfund's Head of Campaigns, said: "We need world leaders to take ambitious and fair action to tackle climate change and provide the finance needed to help poor people adapt and develop sustainably.
"Hope for Creation combines the power of prayer, the passion for social justice and the determination to speak out, and demonstrates to the world that the church has a strong and united voice to bring to development issues."
The day of prayer comes ahead of UN climate talks in Durban at the end of the month.
Tearfund is urging world leaders to be ambitious and secure an agreement on funding to help developing countries mitigate against the impact of climate change.
Mr Niblett said: "Progress on agreeing a fair climate deal for poor communities has been painfully slow.
"On November 6 we will be praying with thousands of others that the process will pick up pace.
"We're asking for Christians everywhere to join us by praying and speaking up for justice for our global neighbours and for action to protect God's creation."