This includes apps that let people use a phone or other mobile device to order pot through an in-app shopping cart, that assist users in arranging delivery or pick-up of weed and that ease the sale of THC products.
"We don't allow apps that facilitate the sale of marijuana or marijuana products," Google says.
The ban came Wednesday in an update to what's restricted in the Google Play Store, first spotted by Android Police.
In a statement emailed to CNET, a Google spokesperson said that to comply with its policy, marijuana apps need to move the shopping cart option outside of the app.
App developers have 30 days to comply.
"We've been in contact with many of the developers and are working with them to answer any technical questions and help them implement the changes without customer disruption," the spokesperson said.
The spokesperson added that Google updates its policies regularly to ensure safe and positive experiences for developers and users, as well as to comply with different legal environments globally.
The shopping cart ban comes despite recreational marijuana being legal in several states, including Google's home state of California. It's also legal for medical uses in a number of other states, though it remains illegal in others and on the federal level.
Originally published May 29, 11:46 a.m. PT.
Update, 12:54 p.m.: Adds comment from Google.