In　some　IoT　applications,　the　sensing　layer　often　collects　images　and　various　temporal　data.　Usually,　some　temporal　data　represents　sensitive　or　private　information.　In　order　to　protect　the　temporal　data,　and　at　the　same　to　reduce　data　traffic　transmitted　through　the　Internet　of　Things,　this　paper　proposes　a　secure　transmission　method　for　sensitive　data　based　on　Arnold　transform　and　steganography　technique.　In　this　method,　an　Arnold　transform　which　is　usually　used　in　scrambling　images　is　applied　to　encrypt　sensitive　sequential　data.　It　is　achieved　by　re-organizing　the　position　of　data　elements　in　a　matrix,　not　necessarily　a　square　matrix.　Then,　the　sensitive　data　in　the　matrix　is　embedded　row　by　row　in　a　carrier　image　using　a　novel　data　hiding　technique,　namely,　capacity　adaptive　algorithm.　Through　the　above　dual　processing,　the　sensitive　data　is　less　likely　to　be　detected　by　a　third　party　during　transmission.　The　experimental　results　indicate　that　the　method　achieves　high　performance　in　safeguarding　the　security　and　privacy　of　sensitive　data.　In　addition,　the　method　offers　numerous　benefits,　including　high　efficiency　and　scalability　in　data　hiding　capacity,　and　low　computational　cost,　making　it　widely　applicable　for　practical　data　transmission.　©　2024　SPIE.