Improving　the　specific　capacitance　and　energy　densityof　a　fiber-shapedsupercapacitor　(FSSC)　is　critical　to　its　applications　as　an　energystorage　device　for　advanced　smart　wearable　electronics.　In　this　paper,a　heterogeneous　poly-(3,4-ethylenedioxythiophene):poly-(styrenesulfonate)/reducedgraphene　oxide/molybdenum　disulfide　(PEDOT:PSS/rGO/MoS2)　fiber　was　prepared　to　achieve　a　high-performance　and　durable　electrodefor　the　FSSC.　As　indicated,　pseudocapacitive　MoS2　was　insitu　grown　on　a　highly　conductive　acid-treated　PEDOT:PSS/rGO　assemblywith　a　hierarchical　structure.　This　structural　design　emphasizes　thewrinkled　morphology　and　high　conductivity　of　the　PEDOT:PSS/rGO　backboneto　maximize　the　MoS2　deposition　and　accelerate　its　electrontransfer,　which　fully　utilizes　the　pseudocapacitance　of　MoS2　and　provides　additional　capacitance　contribution　to　the　obtaineddevice.　Attributed　to　the　synergy,　the　prepared　fiber　electrode　inthe　FSSC　exhibits　high　volumetric/areal　specific　capacitance　(325.8F　cm(-3)/405.3　mF　cm(-2)　at　1　A　cm(-3)　or　1.2　mA　cm(-2))　and　excellent　rateperformance　(82%,　1-10　A　cm(-3)).　The　correspondingdevice　shows　an　ultrahigh　volumetric　energy　density　of　6.9　mW　h　cm(-3)　at　a　high　power　density　of　173.6　mW　cm(-3)　and　an　areal　energy　density　of　8.5　mu　W　h　cm(-2)　at　215.9　mu　W　cm(-2),　together　with　excellentcycle　stability　and　mechanical　flexibility,　outperforming　most　ofthe　previously　reported　FSSCs.　Accordingly,　the　proposed　strategyprovides　a　great　opportunity　to　develop　a　high-performance　FSSC　forfurther　wearable　electronics.