This study compared health-seeking behaviour between poor and better-off people after health sector reform in Cambodia. The survey was conducted in the Prek Dach Health Centre coverage area, which is located in South-east Cambodia. The study population consisted of 257 housewives of reproductive age, selected at random. Data were collected through household surveys with a structured questionnaire. Data collected included socio-demographic information on the housewives, as well as episodes of illness of family members within 30 days prior to the survey. Two indicators, the floor area of living space and a rating scale on asset ownership, were used to identify poor and very poor people. When a family member became ill, subjects most often used home remedies as a first step, followed by self-medication. Subsequently, people used self-medication or the private health sector. Very poor people used the health centre more often than better-off people as a first step. For the second step, use of the health centre was also high among the poor compared with better-off people, although the difference was not statistically significant. Keeping the treatment fees low and abolishing informal fees maintained the affordability of health-centre services for the poor. However, this benefit diminished quickly with distance from the health centre. The significant difference between poor and better-off people disappeared for villages situated more than 2 km from the health centre. Thus, the health centre in the studied area was shown to be effective in providing primary health care to the economically disadvantaged, but only within a limited geographic area.