Traidcraft and Christian Aid have given their backing along with three other charities to the Access To Capital For Rural Enterprises (ACRE) scheme.
ACRE handpicks certain small and medium-sized enterprises (SMEs) across Africa, Asia and South America which have environmentally-friendly principles and growth potential, and invites investors to back them financially.
More than 100 businesses are part of the scheme, like a Ugandan clean energy company which turns waste into solid and gas fuels.
Profits could take ten years or more, but ACRE is encouraging investors to create long-term sustainable change rather than chase short-term profits.
Joanna Heywood, from Christian Aid, said: "We're entering this space because we believe we can bridge the gap between investors who want to make a difference and SMEs which have great potential to grow.
"We also hope to fill the so-called missing middle in which SMEs require investments of between £100,000 and £1 million - amounts that many impact investors find too risky or expensive.
"As charities already working with enterprises across Africa, Asia and Latin America, we have the relationships and the understanding of local contexts that impact investors need, and the footprint and networks to reach hundreds of enterprises."