A semiconductor memory structure includes a substrate, a bit line disposed on the substrate, a dielectric liner disposed on a side of the bit line, and a capacitor contact and a filler disposed on the substrate. The bit line extends in a first direction. The dielectric liner includes a first nitride liner disposed on a sidewall of the bit line, an oxide liner disposed on a sidewall of the first nitride liner, and a second nitride liner disposed on a sidewall of the oxide liner. In a second direction perpendicular to the first direction, the capacitor contact is spaced apart from the bit line by the first nitride liner, the oxide liner, and the second nitride liner, and the width of the filler is greater than the width of the capacitor contact. A method for forming the semiconductor memory structure is also provided.