清华大学建筑与城市研究所多年一直进行北京旧城市改造的研究与实践。近三年来又相继对南锣鼓港地区、北锣鼓港地区现状环境和社会、经济等问题进行了详细的调查，并提出初步规划方案。作者参加了上述大部分工作，在研究调查和规划成果基础上，完成了本篇论文。本文共分三部分：第一部分为背景与立意说明。主要介绍论文的研究的基础，包括北京市旧城改造与保护探索历程简述，本文的基本观点和对旧城改造研究方法的认识、以及南、北锣鼓港地区的现状调查和规划情况简介。第二步分为现状研究与对策探索。以南、北锣鼓港地区为实例，分析新阶段以房地产开发推动的旧城市改造面临问题的新特点。以整体保护为目标，研究文物古迹、平方四合院的保护，及绿化体系、道路系统处理等问题，并提出保护居民利益、审慎处理旧城工业与经济、依据房屋状况制定规划方案等观点。第三步分为 思考与探索。笔者探讨了与旧城改造特别是危旧房改造的有关住房体制改革、房地产市场、政府在旧城改造中的职能等有关政治体制、经济、金融方面的问题，最后提出在危旧房改造过程中十分重视建立和完善中低入居民住房保障体制。

In the Recent three years. A group from the instiute of Architectural and Urban Studies in Tsinghua University has worked on the social and economic conditions of the inner city areas of Beijing and finished a series of planningand researches. Based on this , especially the researche into the Nanluoguxiang and Beiluoguxiang Neighourhoods, the author accomplshed this thesis.The thesis consists of three sections .Section one gaves the background and concepts of this study.Section two includes an analysis of the existing problems and policies to deal with. Using the NanLuoguxiang and BeiLuoguxiang Neighbourhoods as case studies, this part concerns the preservation and upgrading of the physical environments , and the protection of the interests of the residents and comunities. Also recommanded are careful management of neighbourhood economy , plannings based on housing quality and environmental contexts.Section three conterns with the role of govermment in city renewal and real estate development in the city. Also it examines the inteactions amony housing reform, property market and city renewal. The auther arguse that a policy should set up to improve low imcome housing programme.