The study investigated the perception of teachers on the challenges facing the implementation of the new senior secondary education curriculum in Nigeria, using the public and private secondary schools in Ondo State as the focus. To achieve the purpose, a descriptive-survey design was adopted. 2 research questions were raised while 2 hypotheses were formulated. Multi-stage, stratified and simple-random sampling techniques were adopted to select the sample, which consisted of 14 Public Secondary Schools, 14 approved Private Secondary Schools, 84 Public Secondary School teachers and 84 teachers from the approved Private Secondary Schools (6 teachers per school). Data were gathered through the use of a self-developed and structured questionnaire, validated and tested for reliability, correlation coefficient being 0.90. The data were analyzed using Statistical Package on Social Sciences, frequency counts, mean and percentage. The 2 hypotheses were tested using a chi-square statistic. Findings revealed in the public schools that inadequate qualified teachers, lack of workshop, inadequate equipment, lack of laboratory, inadequate instructional materials and infrastructural facilities, among others, faced the implementation of the new curriculum. In the case of the Private Secondary Schools, inadequate funding, erratic power supply, poor students’ background, wrong choice of subjects by students, among others, were the challenges facing the implementation of the curriculum? No significant difference was also found in the perception of male and female teachers, but a significant difference in the case of teachers in public and private secondary schools. The need for government to allocate more funds to the education sector, provide more infrastructural facilities including functional workshops and laboratories, adequate equipment, instructional materials and tools for secondary schools across the state; as well as the production of relevant textbooks for teachers and students, among others, are recommended.