This study evaluated level of work-study approach (wsa) to productivity advancement in Southwest-Nigeria Portable Water Producing Factories (PWPF). Objectives were to, measure productivity trend (PT) and, evaluate managers’ recognition and contribution(s) of wsa to productivity growth. PT was measured from 4 years records provided by 50 employers in 50 PWPF. Questionnaires were used on the employers and 120 employees to measure adopted wsa and impacts with responses reported on the scale of 1 to 5. Data was analyzed using t-test statistical analysis. The best performed PWPF was rated 43.75%. Disloyalty, low remuneration, lack of trainings and unsafe workplace were the major factors reported to have influenced the PT. Machinery Utilization (MeU) maximization was the commonly adopted approach. The employers’ ratings of MeU statistically significantly lower (mean=3.6364, SEM= 0.06913) to that of employees (mean=3.7333 SEM=0.6645) t(169) =0.641, p=0.522. Human resources management (p=0.235) and workers’ performance evaluation (p=0.906) were also significant and rated above average. However, work-method, safe work-practices and work-demands reviews, which were key attributes of ergonomic techniques and workers-related factors (wrf), were not significant, rated below average. The author concluded that neglects of wrf in wsa, must have greatly contributed to the weak PT of the industry and should be properly addressed to enhance productivity growth. Keywords— ergonomic, industry, productivity, water, work-study