Measurement is a essential part in all kinds of industry, especially in manufacturing. But until now, measurement hasn't been located to the core of manufacturing in domestic. This study suggests improvement guide line for the multilateral problems of measuring instrument operation based on the investigation of small and medium-sized enterprises. To use measuring instrument correctly, man who treat it must be accustomed with the structure, the performance, the method. The measuring instrument must be corrected periodically. The correcting-schedule is established with environments with considering accuracy, stability, purpose, condition, and frequency.