Spanish daily newspaper El Pais said on Thursday that Colombia may add 100 soldiers to Spain's 800 troops in northwest Afghanistan next year.
If Colombia did sends troop, it would be the first Latin American country to join Nato operations in Afghanistan.
Foreign troop levels in Afghanistan have increased by more than 10,000 in the past year to around 71,000.
But violence has increased with attacks stemming from neighbouring Pakistan, authorities say.
Taliban fighters are increasingly targeting foreign and Afghan troops with aid agencies saying violence was greater in May and June than in any month since US-led forces helped topple the Taliban government in 2001.
Afghanistan is the world's largest producer of opium, which can be used to manufacture heroin.
Colombia has received billions of dollars in US military aid to support its operations against drug traffickers and the Revolutionary Armed Forces of Colombia (Farc), the country's largest rebel group.