A servo motor control apparatus having a feedback loop includes: an oscillation detecting section, which detects oscillation of the feedback loop, to output an oscillation detection signal; a parameter operating section, which gives an operational instruction to set a control parameter in the feedback loop based upon the oscillation detection signal; and an updating section, which is supplied with a set value for setting a control parameter, and sets the control parameter in the feedback loop while making an update thereon in accordance with the operational instruction given by the parameter operating section, wherein when the oscillation detection signal indicates no detection of oscillation, the parameter operating section gives the updating section an operational instruction to set a control parameter in accordance with the supplied set value, and when the oscillation detection signal indicates detection of oscillation, parameter operating section gives the updating section an operational instruction to set such a control parameter as to narrow a frequency band width of the feedback loop.