This paper examined principals' knowledge of education law in secondary school administration in Delta and Bayelsa States. Ex-post facto research design was used to generate data from a population consisting 617 principals of public secondary schools in Bayelsa and Delta States. The random sampling technique was utilized to sample 124 participants, wherein Bayelsa has 49 selected figures from the three (3) Senatorial Districts of the state while in Delta State, sampled figure consists of 75 across the three (3) Senatorial Districts respectively. The instrument was constructed to generate data from respondents and was analyzed using the Pearson 'r' statistics. Findings indicate that principals in secondary schools in Bayelsa and Delta States have not obtained sufficient legal knowledge of education law in secondary school administration. Therefore, it was recommended that, school principals should be trained in education law because all aspects of school administration involve the application of legal guidelines.