Tourism is expected to be a rewarding activity globally. However, it has been criticized for its inconsistency with the goals of sustainable development. Such criticisms include its implications on the environment; cultural and social life of communities; and the socio-cultural conflicts that arise exclusively from its management styles. The purpose of the study was to investigate the role of community-based tourism organization on the sustainability of tourism sites development. The study was conducted in ten tourism sites namely; Kit Mikayi, Seme Kaila, Abindu shrine, Maasai market, Luanda Magere cultural centres, Paga, Usoma, Dunga, Ndere Island and West Kano Rice scheme in Kisumu County, Kenya. The objectives of the study were: to establish how management by the community influenced the sustainability of tourism sites; to examine how innovation influenced the sustainability of tourism sites; determine how financial resource allocation influenced the sustainability of tourism sites and evaluate the influence of government policy on the relationship between community-based tourism and sustainability of tourism sites. The study was anchored on people centered development theory. The study adopted exploratory research design. A sample size of 383 respondents was derived from a target population of 6360 using the Krejcie-Morgan model. Simple random sampling technique was used. Structured and semi-structured questionnaires, interview schedules, observation checklist, group discussions and document analysis were used for data collection. Both chi- square and regression models were used in the study. The results of community management revealed statistically significant (Fratio = 354.031; p<.05) relation between management and sustainability of tourism sites which accounts to variance of 54% in the sustainability of tourism sites. The result of innovation in community-based tourism sites revealed a statistically significant relationship between innovation and sustainability of (Fratio = 303.602; p<.05) tourism sites accounting for variance of 50.1% in the sustainability of tourism sites.The result of financial resource allocation revealed a statistically significant relationship of (Fratio = 50.545; p<.05) between financial resource allocation and sustainability of tourism sites with a variance of 14.8% in the sustainability of tourism. The result on County government policy revealed that it is a mediating/ intervening factor and is statistically significant (F-ratio = 371.870; p<.05) the relationship between community-based tourism and sustainability of tourism sites. Hence the statistical significance of the regression model (beta(constant)=.196 and beta(policy)= .869; p<.05) was attributed to changes in community-based tourism variables. The study concluded that the variables; innovation beta coefficient 1.201 (p<.05) community management beta coefficient -.319 (p<.05) and financial allocation were statistically significant and made unique contributions to sustainability in community-based tourism sites when other variables were controlled and government policies as intervening factor. The study recommended enhancement of training on management skills and design of community-based tourism organizations that consent to creativity and empowerment of the people and resolve the specific needs of the community.