The study examined the relative effectiveness of Computer Assisted Instruction (CAI) and Classroom Demonstration Technique (CDT) on the performance of students in acid/basetitration under volumetric analysis aspect of the O' level practical Chemistry. A pre-test, post-test control group design was used for the study. A sample of 123 SSS II Chemistry students from three secondary schools in their intact classes in Akure South Local Government Area of Ondo State were used for the study. The three classes were assigned to treatment and control groups. The first group comprising 46 students were taught using Computer Assisted Instruction (CAI), the second group comprising 42 students were taught using the Classroom Demonstration Technique (CDT), while the control group comprising 35 students were taught using the conventional lecture methods (LM). A pre-test was administered before treatment, and after four weeks of instruction, a post-test was administered..Data obtained were analyzed using one way Analysis of Variance and t-test. The results showed that there was a significant difference in the performance of students taught CAI and those taught with CDT (t = 4.95, p <0.05). Also a significant difference existed in the performance of students that were exposed to CDT and those exposed to LM (t = 13.80, p <0.05). There was also a significant difference in the effectiveness of CAI in improving students’ performance in practical Chemistry (F(2,120) = 92.58, p <0.05). It was therefore concluded that CAI was very effective in teaching acid/base titration in practical Chemistry.