The invention provides a portable collection device for a high precision myoelectric signal. The device comprises a power supply as well as a myoelectric signal collection module, a DSP and a Bluetooth connected in sequence. The myoelectric signal collection module comprises a surface electrode, a difference amplifier, a band-pass filter, a main amplifier, an electrical level lifting circuit, a high precision A/D and a buffer circuit. The DSP achieves digital processing as band-pass filtering for the signal, improved self-adaptive FIR notch filter for power-line interference, wavelet threshold denoising and the like as well as control for the whole device using a digital processing method. The Bluetooth sends the signal to a terminal using a digital processing method. The power supply supplies electricity for the whole device. The device combines an analog circuit and the digital processing technology, which enables very high input impedance and common mode rejection ratio, can effectively restrain noise, enables very high precision of the collected signal, has the advantages of low power consumption, is convenient to carry, and can be well applied to the fields of scientific research, wearable device, and the like.