Mechanical Engineering Trade Skills Assessment Instrument (METSAI) is aimed at determining the extent to which students have acquired practical skills before graduation that will enable them get employment for sustainable job security in Yobe state. The study employed instrumentation research design. The populations of the study were 23 mechanical engineering trade teachers and 98 mechanical engineering trade students. The study answered two research questions and tested two hypotheses. The METSAI comprising of practical skills items or operations based on NBTE curriculum and NABTEB syllabus were developed and validated by four experts. Mechanical engineering trade teachers from technical colleges in Yobe state were used for further content-validation of the METSAI items which was tried out on 98 mechanical engineering trade students. Data collected were analyzed using statistical mean, Standard deviation, Split-half technique, t-test and ANOVA. The result of the study showed that 13 basic tasks and 72 practical skills items were found appropriate for the METSAI. The instrument was found to possess a high reliability of 0.92. Based on this result, it was recommended amongst others that teachers and examination bodies (NABTEB, WAEC and NECO) should use METSAI for assessing performance of students in mechanical engineering trade.