ACS712 is a sensor to detect current. ACS712 current sensor can detect noise current or additional current. ACS712 current sensor is one of the sensors commonly used in current measurement circuits. In calibration there is an uncertainty that comes from calibration standards and calibrated devices. Analysis of uncertainty calibration ACS712 current sensor has been done with a purpose for acquired correction value, standard deviation, and uncertainty source estimation, and then the biggest source uncertainty from current measurement can be identified. The result of the analysis can be used to minimalize the possibility of appearance uncertainty source on measurement using the ACS712 current sensor. The analysis was conduct by comparing between ACS712 current sensor and clamp meter standard with a calibration certificate. ACS712 sensor test results have a significant correction when the current higher than 5A, and the temperature will increase. The biggest sources of uncertainty result from type uncertainty and expanded uncertainty