Student motivation is an essential component that plays an instrumental role in their learning. Although academic motivation has received much conceptual and empirical focus, cases of high school students exhibiting lack of willingness to execute the academic tasks are rampant, leading to decline in performance at Kenya Certificate of Secondary Education. The objective was to determine teacher's related motivation factors influencing students' academic performance. A descriptive survey research design was used. The target population was 270 principals, 270 class teachers and 9980 students. Gay's formula of 10% was used to select 27 principals, purposively sample 27 class teachers and used Stratified sampling to select 27 schools. The table by Krejcie and Morgan was used to select 370 students and simple random sampling was applied. Questionnaires were used to gather the needed data. Data was analyzed with the help of SPSS version 19. Analyzed data was represented in table form. 68.5% of teachers and 64.3% of students agreed on expectations, 90.7% of teachers and 84.6% of students agreed that positive teacher-student relationship, 81.5% of the teachers and 86.5% of students agreed that rewards highly motivated students. The research concluded that student motivation by teachers has a positive influence on academic performance.