Some peculiarly low male-to-female suicide ratios have been reported in the Far Eastern populations. This article attempts to investigate whether there are gender differences in suicide risk by socio-demographic factors in Hong Kong, and hereby to explain the low male-to-female suicide ratios. The effects of marital status, duration-of-residence, and occupational status on suicide are first studied by periodic suicide rates in 1990-1992, and 2000-2002, then by Poisson regression. Some interesting results are found: Unlike most findings elsewhere, migration in Hong Kong did not induce suicide; occupational status was negatively related to suicide only for men but not for women; the particularly low male-to-female suicide ratio was not due to a larger protection from marriage for men than for women as reported in the literature, but very probably to a very high suicide rate for the non-working population. The authors suggest some plausible explanations of the findings and hence further research to be conducted.