Sustainable conservation has become popular in tourism, accepted by developers and stakeholders as an economically viable, socially acceptable, and environmentally friendly model for heritage tourism development models. However, heritage tourism encounters challenges like cultural commercialization, deterioration, development pressure, marketing gaps, and insufficient maintenance. Consequently, Kenya has prioritized long-term heritage tourism development goals to realize Vision 2030. This paper examines how market penetration strategies can leverage the sustainable conservation of heritage sites in Nyeri County, Kenya. The study adopted a cross-sectional descriptive survey design, targeting the local community members, tourists visiting the heritage sites, key informants from the local government of Nyeri, officials from the National Museums of Kenya, and site supervisors. The sample size was 762 respondents, 11 were interviewed, and 752 were administered questionnaires. The results of correlation analysis revealed that market penetration strategies exhibited a positive and statistically significant relationship with sustainable conservation (r=0.620, P=0.000), explaining 38.4% of heritage sites' sustainable conservation variations. The study concludes that market penetration catalyzes the sustainable preservation of heritage sites. The study recommends integrating heritage sites into the County's economic plans and employing a comprehensive approach that engages the local community at all stages. This approach should encompass these sites' social, cultural, and economic importance for the local population. Furthermore, the findings highlight the need for a collaborative effort involving multiple government levels and diverse agencies to develop, expand, and market heritage products, with due consideration for biodiversity conservation. Keywords: Biodiversity, Heritage Sites, Market Penetration Strategies, Nyeri County, Sustainable Conservation, Tourism.