A dildo with adjustable girth is provided through a construction including a base, dilating mechanisms, and an elastic membrane which is fit over the dilating mechanisms. The dilating mechanisms are formed from a shaft, lateral bracing supports, and a drive mechanism. The lateral bracing supports are connected along the shaft, forming an inner structure for the elastic membrane. The drive mechanism, when activated, causes the shaft to rotate, which in turn causes the lateral bracing supports to press against and expand the elastic membrane. Preferably, two dilating mechanisms are provided in order to evenly expand the dildo to each side. The drive mechanisms can be either electrically operated (for example a corded input or an internal battery powering a motor) or manually operated (for example a user manually turning a handle to rotate the shaft). An articulated shaft can also be added to allow for bending of the dildo.