The study examined the extent to which principals’ adoption of budgetary control principles (P-ABCP) predict their job performance in public secondary schools in Uyo Local Government Area. The study adopted ex-post facto research design. The population of the study consisted of 41 principals in the 41 private secondary schools in Uyo Local Government Area from which a sample of 21 principals were derived using census sampling approach. Data was collected with designed instruments tagged: “Principals Adoption of Budgetary Control Scale (PABCS)” and “Principals’ Job Performance Scale (PJPS)”. Data collected was analysed using mean while hypothesis was tested with linear regression. The results indicate that the extent of P-ABCP was low (1.88), implying that most of the principals did not utilize feasible budget in administering their schools. The results also showed that the extent to which P-ABCP predicts their job performance in secondary schools was very low. However, though to a very low extent, it was revealed that P-ABCP does significantly predict principals’ job performance. It is concluded the potentials of budgetary control in school administration has shown to be ineffective in enhancing sustainably, the principals’ job performance in public secondary schools. It is recommended that schools owners should mandate the principals to subject their budget and budgetary control plans for assessment before the commencement of an academic session and at the end of the session. This will spur the consciousness of the principals to the importance of having a clear-cut blueprint in the course of achieving effectiveness in school administration.