There is no doubt that science and technology have progressed rapidly in the past decade and it is constantly challenging and refreshing people's understanding of urban environment, human life, and even human nature itself. Meanwhile, its impact on urban environment planning and design should not be ignored and needs to be addressed promptly. The concept of science and technology is self-renewing and has no universal or authoritative definition. In a narrow sense, new science and technology may cover any new materials, technologies, and data invented or discovered by a human; in a broader sense, it might also study new behaviors, emotions, concepts, and philosophy arisen by new materials, technologies, and data. This article explores both positive and negative impacts of science and technology development on urban environment planning and design from nine aspects: image technology, image-tamed design, designers' dilemma, virtual reality, personal mobile electronic devices, big data, human physical limits, public spaces, and nature. Instead of trying to provide definite answers to these questions, this article seeks to encourage readers' to understand and think of these topics through a brief discussion.