Traditional　methods　for　aflatoxin　B1　(AFB1)　detection　are　complex,　time-consuming,　labor-intensive,　and　high　cost.　Moreover,　they　require　sophisticated　large-scale　instrumentation,　which　limits　their　on-site　rapid　detection.　Herein,　phycocyanin　fluorescent　nanospheres　based　on　fluorescence　immunochromatographic　assay　were　developed　for　quantitative　detection　of　AFB1　at　parts-per-billion　(ppb)　levels　in　foodstuffs.　Phycocyanin　and　antiAFB1　monoclonal　antibodies　were　coupled　on　the　surface　of　latex　nanospheres　to　amplify　the　fluorescence　signal　and　improve　the　sensitivity.　The　fluorescence　intensity　was　measured　by　a　self-developed　smartphone-based　reading　system.　Under　the　optimal　conditions,　this　approach　achieved　quantitative　point-of-care　detection　of　AFB1　within　25　min.　The　calibration　curve　for　AFB1　was　linear　in　the　range　of　0.2-48　ppb,　and　the　limit　of　detection　was　0.16　ppb.　The　practical　applicability　of　the　proposed　approach　was　demonstrated　by　the　determination　of　AFB1　in　naturally　contaminated　samples,　and　the　results　were　consistent　with　HPLC　detection.