The success of every construction projects largely depends on the level of commitment of the clients. This study examined the factors influencing the level of clients’ commitment to sustainable construction practices in Nigeria. A questionnaire survey was use to collect data from the public and private construction clients on the level of influence of 16 factors extracted from the literature. A total of 182 valid questionnaires were used for analysis. The result revealed that nine factors with weighted average (W) 0.8≤W≤1 have a high level of influence, whereas seven factors with 0.6≤W≤0.8 have a high-medium level of influence on the clients’ commitment. However, the five most influential factors were: client knowledge and awareness, Cost implication and mechanism of financial involvement, economic value and return on investment, end-user/client perception and preference, and health and safety implications. The result further revealed that there is significant difference on how these factors influence the level of commitment of sustainable construction practices of the public and private clients. The study suggested that the disparity was due to the differences in the level of knowledge, awareness, involvement and commitment of the public and private clients to sustainable construction concept. Hence, it is important to optimize the level of knowledge and awareness of the clients, about the cost, benefits/profits, and health and safety implications of sustainable construction practices so as to promote the level of client’s commitment to sustainable construction practices. It recommended for adequate client involvement throughout the sustainable construction life cycle and a sustained awareness campaign, championed by relevant government agencies and professional organizations through different public programs so as to increase the clients’ commitment and desirability to demand for more sustainable construction projects.