Abstract: A process for producing hollow bodies from oriented thermoplastic material wherein a cylindrical portion of a heated hollow preform which has a bottom thereon is subjected to stretching at a starting temperature which is below the vitreous transition temperature of the thermoplastic material, with the wall thickness of the preform being reduced in the stretching operation. Prior to the stretching operation the preform is heated in the portion in which the stretching effect begins, to a temperature higher than in the portion adjoining same. Stretching is preferably effected along the axis of the preform at different rates such that in the portion of the preform at which stretching begins, stretching is effected at a lower rate than in the portion adjoining same in the stretching direction.