The study investigated Academic and Environmental Stress as Predictors of Academic Achievement of Secondary School Students in Nsukka Education Zone of Enugu State, Nigeria. The need for the study came as a result of increasing rate of poor academic achievement of secondary school students in the study area to which the researchers sought to find solutions. It was guided by two research questions and two corresponding null hypotheses tested at 0.05 level of significance. The research design used for the study was correlation survey design. The population of the study comprised the entire four hundred and sixty secondary school students identify from cumulative record folder of SSII students who have performed poor in English Language and Mathematics in the study area. The entire population of 460 students were used as sample. In this case, there was no sample. This is because the number can be managed. The instrument for data collection were three sets of questionnaire titled “Academic Stress Questionnaire (ASQ)”, “Environmental Stress Questionnaire (ESQ)”; and Academic Achievement Proforma (AAP)”. ASQ and ESQ were properly validated by experts in test development and the internal consistency reliability indices of the items estimated at 0.83 and 0.85 respectively using cronbach alpha method. The data collected were analyzed using coefficient of determination (R2) for research questions, while linear regression was used in testing the hypotheses at <0.05 level of significance. The findings of the study revealed that academic stress predicts positively academic achievement of secondary school students. Also, the study found out that environmental stress predicts positively academic achievement of students. The findings also revealed that there is a significant relationship between academic stress and academic achievement of SSII students in Nsukka Education Zone of Enugu State, Nigeria. Based on the findings, it was recommended among others that secondary school guidance counsellors should organize seminars on academic and environmental stress on academic achievement of students to help improve academic achievement of students.