The paper cited "sources familiar to" the project as saying that mobile carriers Sprint and China Mobile may not release Android handsets until 2009.
Google has long maintained that the first Android-equipped smartphones would hit the market in the later half of 2008. A spokesperson for the company said that Android remains on target.
"We remain on schedule to deliver the first Android-based handset in the second half of 2008 and we are excited to see the momentum continuing to build behind the platform among carriers, handset manufacturers, developers and consumers," the spokesman said.
The Wall Street Journal did not, however, dispute that the first handset could be delivered before the end of the year. The paper said that T-Mobile remained on schedule on to deliver its handset by the end of 2007.
According to the sources, Google has been working so closely with T-Mobile that other vendors have not been able to gain the necessary access and resources to complete their own devices on time.
Google unveiled the open source Android project last year in which Google would provide a software platform while hardware vendors built the handsets and third-party developers created much of the software.
Since then, Google has seen official membership in the Android programme grow to 30 companies, while a recent software design contest garnered more than 1,700 submissions.