Breast　cancer　is　a　type　of　heterogeneous　disease,　which　manifests　as　different　molecular　subtypes　due　to　the　complex　nature　of　tumour　initiation,　progression,　and　metastasis.　Accurate　identification　of　a　breast　cancer　subtype　plays　crucial　roles　in　breast　cancer　management.　Herein,　taking　advantage　of　the　efficient　quenching　properties　of　black　phosphorus　nanosheets　(BPNSs),　in　combination　with　the　high　specificity　of　ssDNA　(or　RNA)　aptamer,　a　fluorometric　duplexed　assay　that　is　capable　of　the　simultaneous　detection　of　two　tumour　markers　within　one　run　is　developed.　When　mixed　with　BPNSs,　the　fluorescence　of　both　FAM　and　Cy3　labelled　aptamers　was　quenched.　The　presence　of　different　subtypes　of　breast　cancer　cells　restored　the　FAM　and　Cy3　fluorescence　in　distinct　patterns　according　to　their　intrinsic　features.　The　proposed　assay　can　precisely　recognise　label-free　breast　cancer　subtypes,　providing　an　efficient　method　for　cell　type　identification　and　guidance　for　subsequent　breast　cancer　treatment.　The　significance　of　the　proposed　study　is　two-fold.　First,　we　provide　a　simple　method　for　sensitive　and　specific　tumour　cell　detection;　secondly,　and　more　importantly,　the　proposed　dual　assay　allows　precise　recognition　of　tumour　cells　and　thus　opens　a　door　for　rapid　characterization　and　sorting　of　a　wide　range　of　tumours　without　using　expensive　instruments.