This book presents the proceedings of the 6th International Conference on Signal Processing and Information Communications (ICSPIC 2023), which was held in Singapore, on February 25-27, 2023. The conference aims to provide a leading international forum for researchers, practitioners, and professionals from the industry, academia and government to share their new ideas, progresses and achievements in signal processing and information communications. The contributions focus on the latest advances, trends and future challenges in analog and mixed signal processing, design and implementation of signal processing systems, compressive sensing, machine learning methods for communications and signal processing, multimedia signal processing, natural language processing, next generation mobile communications, nonlinear signal processing, optical communications, parallel and distributed processing, and more.