台灣曾經發生多起工業污染的重大事件，直到近年政府才逐漸嚴格要求廠商要愛護環境、履行企業社會責任，因此本文旨在討論當廠商重視企業社會責任時，對於廠商利潤以及社會福利的影響。本文假設市場上有兩出口國，本國及外國，國內各有一家廠商，生產時造成區域性污染，將產品全數出口至第三進口國市場，進行價格或數量競爭。 首先在價格競爭分析中發現，不論外國廠商重視環境企業社會責任程度是高或低，本國廠商重視環境企業社會責任會使得本國社會福利增加。當外國廠商關心環境污染的程度較低時，本國廠商重視環境企業社會責任會使廠商利潤減少。即使外國廠商完全忽視污染問題，本國廠商重視環境企業社會責任對社會福利有益。廠商將污染對環境的損害看得跟利潤一樣重要，也能使得本國社會福利增加。當單位污染量增加時，不論廠商們重視環境企業社會責任的程度，都會使本國社會福利減少。 其次，在數量競爭分析中發現，不論外國廠商重視環境企業社會責任的程度高低，當本國廠商重視環境企業社會責任時，都會使得本國廠商利潤減少。惟有當兩出口廠商重視環境企業社會責任的程度差異不大，產生近似勾結減產的效果時，才對本國社會福利有利。在本國廠商重視環境企業社會責任程度高且外國廠商重視環境企業社會責任程度低時，單位污染量的增加會使得本國社會福利增加。;In Taiwan, there are events of industrial contamination have occurred in past decades;however, the authority officially required firms have to care about environment and engage in environmental corporate social responsibility (ECSR) in recent years. In this thesis, we shed lights on how domestic firm′s profit and welfare are affected when firms care about ECSR. We assume that there are two export countries, domestic and foreign, each country has a firm, which exports all products to third import country with Bertrand or Cournot competition and production procedure accompanies local contamination. In Bertrand competition, we find that domestic firm cares about ECSR more will increase domestic welfare, no matter how foreign firm cares about ECSR, even if foreign firm ignores damage from contamination. When domestic firm cares about ECSR more at lower level, domestic welfare increases. In view of domestic welfare, domestic firm considers contamination damages as important as its profits still has positive effect on that. When damage per unit increases, domestic welfare decreases regardless of how firms′ care about ECSR. In Cournot competition, we demonstrate that domestic firm cares about ECSR more will decreases its profits. Only when the difference of level of caring about ECSR between two firms is not large, domestic welfare increases because the effect of producing less seems like collusion exists. Damage per unit increases will increase domestic welfare when the level of domestic firm cares about ECSR is high and foreign firm cares about ECSR is low.
