Gender disparities are compared in each survey (below). The data from each survey shows that 70-80% of all hikikomori are males.

From these surveys, it can be seen that 70-80% of all hikikomori are males. From this finding, we can assess that there is a significant association between hikikomori and characteristics of the male gender (i.e., increased societal pressures for males (vs. females) to financially support their family in the future; such high pressures may lead to hikikomori behavior).

Hikomori and the Female Gender

While data shows that 70-80% of all reported hikikomori are males, hikikomori affects both genders and females are thought to be underreported. Because it is traditionally more societally acceptable for females to remain inside the home to do household work, Japanese parents may feel less urgency to report their daughters' hikikomori behavior. Parents tend to hope that their daughters will someday marry and be financially supported by their future husband, and thus they feel a stronger urgency for sons to recover from hikikomori behavior. While female hikikomori do exist, the causes of hikikomori in males and females are likely to differ, but more research is needed in this area.

Data shows that 76.4% are male. This survey, "The Survey of "social withdrawal" about Consultation and assistance situation" " followed "the Guidelines for Regional Mental Health Activities involving "hikikomori" in Teens and Adolescents in their 20's."
(note: the definition of hikikomori used in the "Hikikomori Guideline" includes hikikomori behavior resulting from developmental disorders and mental illnesses (which is excluded in the Tamaki Saito's definition of hikikomori).
Reference: "The Survey of "social withdrawal" about Consultation and assistance situation"(Japanese)

Data shows that 86% of hikikomori are male. Data is taken from patients who underwent medical examinations in Saito Tamaki's (author or Societal Withdrawal) research lab.
Reference: Tamaki Saito, 1998, Hikikomori: Adolescence Without End, Japanese(amazon), English(amazon)

Data shows that 79.5% of hikikomori are male. Data is taken from the Saitama Prefecture Office of Health Welfare's "Report of Factual Investigations on Hikikomori" (2002). The unique characteristic of this survey is that the analyses of the medical diagnoses are conducted using the official definition of hikikomori. Out of the 723 cases sampled, actual analyses was only conducted on the 131 cases after excluding those associated with mental illnesses. This survey is particularly relied upon because of this (exclusion).
Reference: Saitama Prefecture Mental Health and Welfare Association(埼玉県精神保健福祉協会)
Sohei IDE's Study Note(Japanese)
Note: This report generally is not discloed.

Data shows that 68.7% of hikikomori are male. Data is taken from the Oita Prefecture Office of Health Welfare's "Report on Factual Investigations of Hikikomori" (2004). The unique characteristic of this survey is that "hikikomori" is not limited to adolescents. The data includes a wider age range; a maximum age of 73 years and a 5.7% increase in individuals 45 years and older. Though still lacking factual support, it is believed that this older population suffers from hikikomori due to a mixture of reasons including mental disorders and anxieties of retired employees and housewives.
Reference: Sohei IDE's Study Note(Japanese)

Data shows 83.7% of hikikomori are male. Data is taken from the "Hikikomori Investigation Report" conducted by the National Hikikomori KHJ Parental Association, NPO, who surveyed its members. By the nature of a parental gathering (KHJ Parental Association), the majority of cases reported within the association are long-term hikikomori. The reasonings are that parents of short-term hikikomori are less inclined to join and seek help from the Parental Association, and it further argued that the main role of the Parental Association is to motivate parents to deal with longer-term hikikomori. The Parental Association does not deal with gender disparaties, largely due to their focus on the longer-term problems of hikikomori which they do not associate with gender differences.
Reference: Motohiro Sakai(Tokushima University) Webpage "Hikikomori Investigation Report"(PDF,Japanese)
Reference: KHJ Parental Association(Japanese)

Data shows 77.1% of hikikomori are male. Data is taken from all 14 consulting organizations in the Tokyo area's Tama District and Yokohama City. The definition of hikikomori is taken from the "Guideline Definition," and therefore includes development disorders and mental illnesses.
Reference Link: Yoji Yoshida, et.al., "Research Investigation on Situations of the Hikikomori Individual and Family Members in Cases of 'Social (PDF, Japanese)
Reference: Sohei IDE's Study Note(Japanese)