The invention discloses a bottom die movement control mechanism of a rotary bottle blowing machine die rack. The bottom die movement control mechanism comprises a die rack support, a swing arm, a horizontal guide rail and a bottom die support, wherein a crank connecting rod structure capable of driving the bottom die support to reciprocate along the vertical direction is arranged between the swing arm and the bottom die support; a ball sliding block capable of restricting the bottom die support to move along the vertical direction and a ball guide rail are arranged between the bottom die support and the die rack support. By virtue of reciprocating swing of the swing arm along the locus of the horizontal guide rail, the crank connecting rod structure drives the bottom die support to reciprocate along the vertical direction; by use of only one horizontal guide rail, the opening and closing of a forehead die rack on the die rack support and the ascending and descending of the base on the bottom die support are completely controlled, a bottom die guide rail which is traditionally used for controlling the ascending and descending of the bottom die support is omitted; under a condition of same rotation speed, the noises and vibration of the bottom die movement control mechanism are more less than those generated by a die rack when two different guide rails are respectively used for controlling respective movement of the movement bottom die and the opening and closing of the die rack in the prior art, so that a great improvement space is provided for the operation reliability and speed of machines.