Ceramidases are a group of enzymes that catalyze hydrolysis of ceramides to generate fatty acid and sphingosine. In this study, we report the cloning and characterization of the rice small brown planthopper Laodelphax striatellus neutral ceramidase (nCDase), LsnCer. LsnCer was identified by sequencing the transcriptome of Laodelphax striatellus. LsnCer is a protein of 717 amino acids with a predicted molecular weight of 79.3 kDa. Similar to other known nCDases, LsnCer has a pH optimum at 8.0 and a temperature optimum at 37 °C for its in vitro activity. LsnCer activity is inhibited by Zn2+ significantly and Fe2+ slightly. LsnCer has broad substrate specificity with preference for ceramides with a medium acyl-chain or a mono unsaturated long acyl-chain. Infection with the rice strip virus (RSV) or treatment with insecticides significantly increased LsnCer mRNA expression and its enzymatic activity in L. striatellus. These results suggest that LsnCer is a bona fide nCDase that may have a role in adaption of L. striatellus to environmental stresses.