Manufacturing methods for a low temperature poly-silicon array substrate and for a low temperature poly-silicon thin-film transistor are provided. The manufacturing method for the low temperature poly-silicon array substrate includes: providing a substrate; forming a poly-silicon semiconductor pattern on the substrate; a first channel region, a first source region and a first drain region being formed on a first portion of the poly-silicon semiconductor pattern that corresponds to the first thin-film transistor and a second thin-film transistor; forming a gate insulation layer; performing an activation treatment; forming a gate on the gate insulation layer after the activation treatment; forming an interlayer insulation layer between the gate insulation layer and the gate; performing a hydrogen treatment; forming a source/drain pattern on the interlayer insulation layer after the hydrogen treatment, and connecting the source/drain pattern to the source region and the drain region in the poly-silicon semiconductor pattern via a through hole.