An envelope waveform producing circuit includes a ROM for storing a plurality of groups of parameter data, each group of parameter data defining a waveform of an envelope which includes data representing at least one of an attack rate and an attack level and data representing at least one of a decay rate and a sustain level, an address designator, connected with the ROM, for reading out a desired group of parameter data from the ROM to cause an envelope waveform to be produced in accordance with the parameter data read out, an UP/DOWN counter for selectively counting up and down from a preset value, a coincidence detector, connected with the UP/DOWN counter, for detecting coincidence between a counted value of the UP/DOWN counter and a predetermined value, a control circuit, connected with the UP/DOWN counter and the address designator, for controlling the address designator to read out desired parameter data and for controlling the UP/DOWN counter to count up or down from the preset value, and activation or deactivation of the UP/DOWN counter.