中文摘要：

本文分析了新新贸易理论的提出背景、核心思想、中国经验和面临的挑战，以及多重异质性模型的理论和实践意义。随着经济全球化的深化，企业已经成为出口行为的主体，基于企业层面异质性的新新贸易理论正在构建传统贸易理论的微观机理。新新贸易理论的核心理论思想是企业层面异质性是预测和解释贸易行为的基础，其经典模型是生产率异质性模型。这一模型极具理论启发，但也遇到了中国现实的挑战；拓展生产率异质性模型，发展多重异质性模型不仅可以提升新新贸易理论的现实解释力，而且可以释放更大的理论创新空间。

英文摘要：

This paper analyzes the background, the core idea, China experience and challenge of new-new trade theory. It also proposes the theoretic and practical significance of multiple heterogeneity model. With the deepening of economic globalization, firms have become the main part of export behavior. Based on firm heterogeneity, new-new trade theory is constructing the micro mechanism of the traditional trade theory. The main idea of new-new trade theory is that, firm heterogeneity is the basis of forecasting and explaining trade behavior and productivity heterogeneity model is its classical model. This model is inspiring but also met challenge from China＇s reality. Therefore, expanding productivity heterogeneity model and developing multiple heterogeneity model not only can promote the interpretation of new-new trade theory, but also can release more space of theoretical innovation.