Background With the increasing of ageing population, tuberculosis in the elderly brings a challenge for the tuberculosis (TB) control in China. Enough social support can promote the treatment adherence and outcome of the elderly patients with TB. Exploring effective interventions to improve the social support of patients is of great significance for TB management and control. Methods A community-based, repeated measurement trial was conducted. Patients with TB >65 years of age were allocated into the intervention or control group. Patients in the intervention group received comprehensive social support interventions, while those in the control group received health education alone. The social support level of patients was measured at baseline and at the first, third and sixth months during the intervention to assess the effectiveness of comprehensive social support interventions. Results A total of 201 patients were recruited into the study. Compared with the control group, social support for patients in the intervention group increased significantly over time ((group*time)=0.61, P<0.01) in the following three dimensions: objective support ((group*time)=0.15, P<0.05), subjective support ((group*time)=0.32, P<0.05) and support utilisation ((group*time)=0.16, P<0.05). The change in the scores in the control group was not statistically significant. Conclusions The intervention programme in communities, including health education, psychotherapy and family and community support interventions, can improve the social support for elderly patients with TB compared with single health education. Trial registration number ChiCTR-IOR-16009232