The announcement wiped out more than 10% Twitter's stock value on Wednesday US time.
According to various news outlets including AAP Twitter, founded in San Francisco, posted a better-than-expected quarterly revenue of US$243 million ($271 million) in its first results as a public company.
But the social media company told shareholders it lost $US511 million ($573 million) in the last three months of last year.
Investors also focussed on slowing user growth, as well as an arresting decline in timeline views.
Twitter's chief financial officer Mike Gupta told reporters and investors more than 90% of its revenue comes from advertisers and that is set to grow strongly.
"Advertisers are increasingly recognising that conversations on Twitter provide a valuable opportunity to connect with consumers on Twitter in real time and in Q4 [the fourth quarter] we saw a record number of retailers flock to Twitter to do just that," he said.
Facebook on the other hand is performing very strongly, and is booming as an advertising platform.