The zero error is an important parameter of the moisture balance, which directly affects the weighting accuracy of measuring the moisture. A method for compensating the zero error of moisture balance based on long-short term memory ( LSTM) network was proposed. The mechanism of the zero error of moisture balance was analyzed, and the prediction model of zero error based on the double layer LSTM was established by using historical zero error data. This proposed model was used to compensate the zero error of the moisture balance with some loads and without load respectively, where the measuring range of the moisture balance is 200 g and its resolution is 1 mg. The experimental results show that the maximum error of the compensated moisture balance is about 6 mg, which is much smaller than before. The experiments have verified the effectiveness of this method.