This study focuses on the effects of various spindle diameters and the spindle working period on the properties of 100% viscose MVS yarns. MVS yarn samples produced with four levels of spindle diameter, 1.1, 1.2, 1.3, 1.4 mm and five levels of the spindle working period: 0, 1, 2, 3, 4 month, were evaluated on the basis of unevenness, hairiness, elongation at break, tenacity and work-of-break (B-work) values. The results indicate that a large spindle diameter results in high hairiness, as well as low unevenness and tenacity values. The wear of the spindle increases with an increasing working period The wear is mainly seen in two different zones: the proximal edge of the hole entrance (tip zone), and the hole surface of spindles. After a four month working period, spindle wear becomes a more critical factor for 100% viscose MVS yarns.