Flicker envelope tracking has many important applications in distribution systems for either flicker meters or flicker compensators. This paper introduces a new application of the adaptive linear neuron (ADALINE), and the recursive least square (RLS) algorithm for flicker envelope tracking. The ADALINE is characterized by a light computational demand, unlike that of existing techniques; the RLS algorithm betters the ADALINE by its fast convergence and robust tracking performance. Both the ADALINE and the RLS algorithm give accurate results even under rapid dynamic changes. The paper investigates the effects of different parameters on the ADALINE and the RLS algorithm. Extensive simulations of the proposed flicker tracking algorithms are conducted to evaluate their performance. The ADALINE and the RLS algorithm are examined by tracking the flicker produced by a resistance welder in a simple distribution system simulated in the PSCAD/EMTDC package.