To investigate the possible roles of LAMMER kinase homologue, Lkh1, in Schizosaccharomyces pombe, whole proteins were extracted from wild type and lkh1-deletion mutant cells and subjected to polyacrylamide gel electrophoresis. Differentially expressed proteins were identified by tandem mass spectrometry (MS/MS) and were compared with a protein database. In whole-cell extracts, 10 proteins were up-regulated and 9 proteins were down-regulated in the mutant. In extracellular preparations, 6 proteins were up-regulated in the lkh1 (+) null mutant and 4 proteins successfully identified: glycolipid anchored surface precursor, β-glucosidase (Psu1), cell surface protein, glucan 1,3-β-glucosidase (Bgl2), and exo-1,3 β-glucanase (Exg1). These results suggest that Lkh1 is involved in regulating cell wall assembly.