The population of Hong Kong reached 7.07 million as of June last year, about 360,000 more than a decade ago, according to the latest census figures.
Around 6.86 million were usual residents and 210,000 were mobile residents - permanent residents who have stayed in Hong Kong for at least one month but less than three months within six months of the census being conducted.
The gender imbalance is also growing slightly, with more females in the territory than males.
The ratio dropped from 960 males to 1,000 females in 2001 to 876:1,000 in 2011.
But after excluding the number of foreign domestic helpers, the ratios for 2001 and 2011 were put at 1,012:1,000 and 939:1,000 respectively.
The proportion of the never-married population aged 20 to 49, the prime marriageable ages, increased substantially from 39.3 percent to 46.8 percent for men and 34 to 38.9 percent for women.
But the increases were found to have moderated in the past five years.
"Being able to find a spouse is a personal matter and not only related to the sex ratio," Census and Statistics commissioner Lily Ou- Yang Fong said yesterday.
The results also show that men and women tend to get married the first time at the age of 31.1 and 28.8 respectively, about one year later than 10 years ago.
Ou-Yang said the social and economic reasons behind the trend may be found in different studies but are not reflected in the census results.
The data also show that the population is continuing to age, with the median age reaching 41.7, compared with 36.7 in 2001.
She said the trend is due to low fertility and mortality rates in the past 10 years.
It is expected the median age of the population will continue to grow over the next 10 years as the baby boomers, born post-war and aged 55 to 64, become senior citizens.
"The situation is not serious compared to Japan on the international perspective," said Ou-Yang, referring to Japan's 21.2 percent of population aged 65 or older in 2007.
According to the census, 13.3percent of the population was aged 65 or above last June.
Comparing the 2001 and 2011 population pyramids, the 2011 base has shrunk due to a reduction in the proportion of children aged below 15.
From 2006 to 2011, population growth remained slow with an average annual growth rate of 0.6percent as compared with 0.4percent during 2001 to 2006.