Abstract: Measurement uncertainty is a non-negative parameter characterizing the dispersion of the quantity values being attributed to a measurand, and it is associated with the measurement result and is the quantitative expression for the quality of the measurement result. Measurement uncertainty indicates the reliability of the measured values. Measurement uncertainty applies to all kinds of the measurement fields including science, technology, and engineering. The research on theory and application of measurement uncertainty have continuously been deepened. As the International System of Units has been closely linked with measurement and used all over the world, measurement uncertainty will play an important role in the measurement fields. The spread of measurement uncertainty is a specific and hard and basic work, which is involved in many fields and is difficult, and then it should be paid attention. This article gives a good overview about development and application.

Key words: Measurement uncertainty, GUM, MCM, Development and application