These are all the zips released in the 1.5.x series up to 1.5.7d.

For information about the required versions of PHP and MySQL for each release, please see the server requirements page.

Zen Cart version 1.5.8 and 1.5.8a can be found on Github:

Zen Cart v1.5.0 to 1.5.7 can be downloaded using these links: