Cleistocactus samaipatanus grows to 1.5 m (4.9 ft) tall, it has multiple long, forms branched groups from the base with some upright trunks with diameters of 3.5 to 4 cm (0.11 to 0.13 ft), narrow columnar green stems with pale gold spines.

The 4 cm long flowers are very crooked and have narrow, looser and reflexed, pointed sepals that are purple.

They are densely woolly white and brown with an attached flower remnant and contain tiny blackish-brown or black seeds.

Cleistocactus samaipatanus is widespread in the lowlands of the Bolivian department of Santa Cruz at altitudes of 1000 to 2000 meters.

[1] In cultivation in the UK, this plant has gained the Royal Horticultural Society's Award of Garden Merit[3] (confirmed 2017).