In recent years, high labour costs and the inconsistency of manual asembly have led to the wider acceptance of robotic assembly in product manufacturing. Planning robot assembly tasks requires a method of estimating robotic cycle time. Identifies some of the relationships between robot assembly time and manual assembly time, in order to develop a method of robot assembly time estimation based on manual assembly times. Uses methods time measurement (MTM) and robot time and motion (RTM) as the basis of comparison. Uses two case studies to evaluate the approach.