According to the 2010 Census, the population of Siren City was 806 people. The city's population density was 243.7 people per square mile (631.2 people per square kilometer). There were 490 occupied housing units in Siren. Of these, 376 were owner-occupied homes. Another 153 were renter-occupied homes. Overall, the city had a 4.7% homeowner vacancy rate and a 10.9% rental vacancy rate.
The overall population was very diverse and the median age was 42 years. There were approximately 11.7 children per 100 people. There were also 14.8% adults and 6.7% seniors. The majority of the population was male, but there were also a lot of females. In this way, the population of Siren City was similar to the state's overall statistics.