A seat slide apparatus for a vehicle, comprising: a first rail; a second rail movable relative to the first rail; a lock member restricting a relative movement between the first rail and the second rail; a plurality of engagement bores formed at a bottom wall portion of the first rail at predetermined intervals in a longitudinal direction of the first rail and including a rear end engagement bore that extends in a rearward direction of the vehicle from a point away from one of the engagement bores arranged next to the rear end engagement bore by the predetermined interval, a front end portion of the rear end engagement bore being further positioned in a forward direction of the vehicle than a rear end of the second rail in a state where the second rail is positioned at a foremost position relative to the first rail, a rear end portion of the rear end engagement bore being exposed to a rear of the rear end of the second rail, the rear end engagement bore being arranged at a rearmost side among the engagement bores; a memory member movably supported within an inner void that is formed between the first rail and the second rail in the longitudinal direction of the first rail, the memory member being prevented from moving by an engagement with one of the engagement bores; a holding member (60, 50) fixed to the second rail and holding the memory member to move integrally with the second rail in a state where a restriction of the relative movement between the first rail and the second rail by the lock member is released on a basis of an operation of an operation handle, the holding member (60, 50) holding the memory member to engage with one of the engagement bores in a state where the restriction of the relative movement between the first rail and the second rail by the lock member is released in association with a forward folding operation of a seat back of a seat configured to be fixed to the second rail; and an auxiliary bracket fixed to the bottom wall portion of the first rail and restricting a movement of the memory member that engages with the front end portion of the rear end engagement bore towards the rear end portion thereof. a first rail; a second rail movable relative to the first rail; a lock member restricting a relative movement between the first rail and the second rail; a plurality of engagement bores formed at a bottom wall portion of the first rail at predetermined intervals in a longitudinal direction of the first rail and including a rear end engagement bore that extends in a rearward direction of the vehicle from a point away from one of the engagement bores arranged next to the rear end engagement bore by the predetermined interval, a front end portion of the rear end engagement bore being further positioned in a forward direction of the vehicle than a rear end of the second rail in a state where the second rail is positioned at a foremost position relative to the first rail, a rear end portion of the rear end engagement bore being exposed to a rear of the rear end of the second rail, the rear end engagement bore being arranged at a rearmost side among the engagement bores; a memory member movably supported within an inner void that is formed between the first rail and the second rail in the longitudinal direction of the first rail, the memory member being prevented from moving by an engagement with one of the engagement bores; a holding member (60, 50) fixed to the second rail and holding the memory member to move integrally with the second rail in a state where a restriction of the relative movement between the first rail and the second rail by the lock member is released on a basis of an operation of an operation handle, the holding member (60, 50) holding the memory member to engage with one of the engagement bores in a state where the restriction of the relative movement between the first rail and the second rail by the lock member is released in association with a forward folding operation of a seat back of a seat configured to be fixed to the second rail; and an auxiliary bracket fixed to the bottom wall portion of the first rail and restricting a movement of the memory member that engages with the front end portion of the rear end engagement bore towards the rear end portion thereof.