Aimed at the problem of cold resulted from sleeping fidget about infants, this paper explored the mechanism of the sleeping fidget, and presented the relational model between the sleeping fidget and temperature, humidity, and their changes. Authors developed the data acquisition system of the temperature and humidity based on the digital sensor, acquired lots of data about the temperature/humidity and the corresponding fidget degree, designed the neural networks model construct through analyzing the relation among three kinds of data. On this basis, the NN model was trained with the experimental data based on MATLAB NN Toolbox. The model verification shows that the sleeping fidget model can effectively implement sleeping fidget monitoring.