A novel actinomycete, designated strain NEAU-GRX6T, was isolated from mucky soil collected from a stream of Jinlong Mountain in Harbin, Heilongjiang Province, north China, and characterized using a polyphasic approach. The isolate formed irregular sporangia containing motile sporangiospores on the substrate mycelium. The whole-cell sugars were xylose, glucose and galactose. The predominant menaquinones were MK-9(H6), MK-10(H4) and MK-9(H4). The major fatty acids were C16:0, C15:0, C18:1ω9c, C17:1ω7c and C18:0. The phospholipids were diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol and phosphatidylinositol. The DNA G+C content was 67 mol%. 16S rRNA gene sequence similarity studies showed that strain NEAU-GRX6T belonged to the genus Actinoplanes, being most closely related to Actinoplanes palleronii IFO 14916T (97.80% similarity) and Actinoplanes missouriensis NBRC 102363T (97.76%). However, the low observed levels of DNA-DNA relatedness allowed the isolate to be differentiated from the above-mentioned species of the genus Actinoplanes. Moreover, strain NEAU-GRX6T could also be distinguished from A. palleronii IFO 14916T and A. missouriensis NBRC 102363T by phenotypic characteristics. Therefore, it is proposed that strain NEAU-GRX6T represents a novel species of the genus Actinoplanes, for which the name Actinoplanes lutulentus sp. nov. is proposed. The type strain is strain NEAU-GRX6T (=CGMCC 4.7090T=DSM 45883T).