The study determined the effects of Computer Numerical Controlled Machines on Students' Achievement and Interest in Mechanical Engineering Craft Practice in Technical Colleges in Rivers State using Machining Processes - turning, drilling and milling as variables. Nine (9) research Questions guided the study and nine (9) hypotheses were tested at .05 level of significance for the study. The study employed Research and Development incorporating quasi-experimental research design. The population for the study was 133 National Technical Certificate class two (NTC II) mechanical engineering craft practice students from four Technical Colleges in Rivers State for the 2018/2019 session. These students in their intact classes were assigned to sixty-seven (67) for experimental group (Computer Numerical Controlled Machines) and sixty-six (66) for control group (Traditional/Conventional machines). Machining Process Achievement Test and Machining Process Interest Inventory were developed, validated and used for data collection. Research Questions were answered using means and standard deviation while hypotheses were tested using Analysis of covariance (ANCOVA) at .05 level of significance.