The electrocardiogram (ECG) has the considerable diagnostic significance, and applications of ECG monitoring are diverse and in wide use. Noises that commonly disturb the basic electrocardiogram are power line interference (PLI), instrumentation noise, external electromagnetic field interference, noise due to random body movements and respiration movements. It is essential to reduce these disturbances in ECG signal to improve accuracy and reliability. it is difficult to apply filters with fixed filter co-efficient to reduce these noises. Adaptive filter technique is required to overcome this problem as the filter coefficients can be varied to track the dynamic variations of the signals. Adaptive filter based on the least mean square (LMS) algorithm is applied to noisy ECG to reduce 50 Hz power line noise and motion artifact noise. The removal of power line interference from most sensitive medical monitoring equipments can also be removed by implementing various useful techniques. The power line interference (50/60 Hz) is the main source of noise in most of bio-electric signals. the removal of power line interference and other single frequency tones from ECG signal using the advanced adaptive filtering technique with LMS (least mean square) algorithm. it is based on digital signal processing (DSP) techniques with MATLAB package, with the emphases on design of adaptive LMS algorithm.