In this experimental work, the performance of a nanofluid-based solar still equipped with a dual-axis solar tracker system (STS) has been investigated through various viewpoints, i.e., daily and nightly fresh-water production, hourly and daily efficiency and cost. The proposed solar still consists of a conventional solar still (CSS), three Fresnel lens concentrator, and an active automatic STS. Moreover, the effects of deionized water, MWCNTs/water nanofluid with two mass fractions of 0.15 and 0.3%, as the heat transfer fluid (HTF), are studied on fresh-water productivity to evaluate the appropriate HTF type. The daily, nightly, and total fresh-water produced by the CSS with internal condenser is found to be 2180, 560, and 2740 mL/(m2·day), respectively. However, the CSS integrated with STS and Fresnel lens can produce daily, nightly, and total fresh-water of 5310, 1080, and 6390 mL/(m2·day), respectively. In addition, the results indicate that using MWCNTs/water nanofluid with a mass fraction of 0.3% enhances fresh-water productivity by 31.6, 7.4, and 27.5%, respectively, compared to that of pure water as HTF. The results reveal that by using the nanofluid with a mass fraction of 0.15 and 0.3%, the daily average efficiency is increased about 9.56 and 17.85%, respectively, compared to that of pure water as HTF.