The purpose of this study was to investigate the practice and challenges of school leadership in secondary schools of the Guji Zone. In order to meet the objectives of the study, a descriptive survey design and mixed method was employed. Six Woredas were addressed by this study. From 133 populations, the researcher selected forty (40) teachers by simple random sampling techniques and Eighteen (18) principals, six (6) school cluster supervisors and six (6) education head office by comprehensive sampling techniques. Totally 70 (52.63%) sample respondents were incorporated in to the study as a primary sources of data. Questionnaires, interviews and document analyses were used for the purpose of collecting relevant data. Data obtained through questionnaires were analyzed using statistical tools like frequency, percentage, mean, standard deviation and an independent sample t-test to use p-value. Moreover, data gathered through interview and document analysis were considered to supplement the questionnaires in narrative form. The finding of this study revealed that the practices of school principal functions in school were high only by interest but not properly implement in the school due to lack of specialized fields educational leadership, lack of staff participations in decision making, lack of identifying training needs of teachers, and work over load on administrative activities of principals in the sampled secondary schools of Guji Zone. Because, (72.22%) school principals were subject graduate who lack knowledge, skill and training aspects of instructional leadership profession. Based on the findings, the researcher was concluded that the practices of school leadership functions were ineffective in the sampled secondary schools of Guji zone. It is good if school leadership communicate the school goals and objective effectively and clearly to the school community and parents because understanding of school goal and objective by stakeholders make easier for the good achievement of school effectiveness.