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This study examines the effects of ownership, competitiveness, firm size and research and development (R&D) expenditure on exports of Iran's vehicles manufacturing industries. A panel data model is set up using 4-digit codes of the International Standard Industrial Classification (ISIC) related to vehicles manufacturing industries in Iran over the period 2005-2013. The dynamic panel data technique and two-stage generalized method of moments (Arellano and Band method) are used to estimate the econometric model. The estimation results indicate positive and significant effects of private ownership, R&D expenditure and competitiveness on export intensity in Iran's vehicles manufacturing industries. According to the positive effect of the private ownership on exports, facilitating the entrance of the other private firms aiming at producing and exporting of vehicles’ products can be a considerable step for promoting foreign trade in Iran. In addition, findings show that real exchange rate has no significant effect on export intensity among mentioned industries. Moreover, higher tariff rates on imports of vehicles in Iran and higher relative prices of vehicles compared to world prices have limited the potential of exporting the products of such industries.