The company is updating its financial services-related ad policies to ban any advertising about cryptocurrency-related content, including initial coin offerings (ICOs), wallets, and trading advice, Google's director of sustainable ads, Scott Spencer, told CNBC.
That means that even companies with legitimate cryptocurrency offerings won't be allowed to serve ads through any of Google's ad products, which place advertising on its own sites as well as third-party websites.
This update will go into effect in June 2018, according to a company post.
Google's hard-line approach follows a similar ban that Facebook announced earlier this year.
This news comes as Google releases its annual "trust and safety" ads report.
Google said it took down more than 3.2 billion ads in 2017 that violated its policies, which is nearly double the 1.7 billion it removed the year before.
Google parent company Alphabet makes roughly 84 percent of its total revenue from advertising, so convincing advertisers that its ecosystem is safe and effective is critically important.