The meeting was held on the sidelines of semiannual meetings of the International Monetary Fund and World Bank in Washington on Friday.
The two officials conferred on international and bilateral affairs, emphasizing the importance of boosting economic relations and in particular the private section of the two countries.
"Iran is ready to help building the infrastructure of Sri Lanka," Hosseini stated.
Rajapaksa, for his part, thanked the Iranian technical assistance and called for development of technical cooperation between the Iranian and Sri Lankan companies.
Iran and Sri Lanka have had official diplomatic relations since 1961.