The Komatsu PC20MRX-1, part of the MRX Series, is a compact excavator engineered for reliability and performance in demanding work environments. This machine features a robust diesel engine and a hydrostatic transmission with variable gears, providing efficient power delivery for a variety of tasks. With an operating weight of 2060 kg and dimensions suitable for tight spaces, including a transport height of 2460 mm and width of 1550 mm, it offers versatility for construction, landscaping, and utility work. Its design emphasizes operational ease and durability, making it a dependable choice for professional applications. This Workshop Service Repair Manual provides comprehensive guidance for the Komatsu PC20MRX-1. It covers essential maintenance procedures, detailed troubleshooting steps, and critical technical specifications, including hydraulic system details like the main pump flow rate of 56.0 L/min and a variable displacement piston pump. The manual is designed to assist owners, mechanics, and technicians in performing routine maintenance, diagnostics, and repairs, ensuring the optimal performance and longevity of the equipment. All information is presented in English for clarity and ease of use.