Molybdenum　disulfide　(MoS2)　has　attracted　increasing　research　interest　recently　due　to　its　unique　physical,　optical　and　electrical　properties,　correlated　with　its　2D　ultrathin　atomic-layered　structure.　Until　now,　however,　great　efforts　have　focused　on　its　applications　such　as　lithium　ion　batteries,　transistors,　and　hydrogen　evolution　reactions.　Herein,　for　the　first　time,　MoS2　nanosheets　are　discovered　to　possess　an　intrinsic　peroxidase-like　activity　and　can　catalytically　oxidize　3,3′,5,5′-tetramethylbenzidine　(TMB)　by　H2O2　to　produce　a　color　reaction.　The　catalytic　activity　follows　the　typical　Michaelis-Menten　kinetics　and　is　dependent　on　temperature,　pH,　H2O2　concentration,　and　reaction　time.　Based　on　this　finding,　a　highly　sensitive　and　selective　colorimetric　method　for　H2O2　and　glucose　detection　is　developed　and　applied　to　detect　glucose　in　serum　samples.　Moreover,　a　simple,　inexpensive,　instrument-free　and　portable　test　kit　for　the　visual　detection　of　glucose　in　normal　and　diabetic　serum　samples　is　constructed　by　utilizing　agarose　hydrogel　as　a　visual　detection　platform.　©　2014　the　Partner　Organisations　2014.