It surpassed London's UNESCO World Heritage site Royal Botanic Gardens Kew, and Tokyo's Shinjuku Gyoen that both had over 700,000 posts under their hashtags on Instagram, according to a survey by British tour operator and travel site Titan Travel.
The site said Gardens by the Bay is the only garden to have over one million Instagram posts.
The nature park spans 101 hectares and consists of three waterfront gardens, the largest of which is the Bay South Garden, which houses two cooled conservatories, as well as several so-called super trees.
Recently, it was named the most loved tourist attraction in Asia by Tripadvisor readers.