ICP-MS is powerful in evaluating elemental species at the single-cell level, where high throughput/efficiency/precision are the keys for achieving statistically significant information based on massive data. We report an ultrahigh-throughput single-cell sampling system, consisting of a 3D spiral-helix tubing array to facilitate single-cell focusing into an orderly flow by inertial lift force and Dean drag force. The spiral-helix array ensures a superb single-cell sampling rate of 40 000 cells min-1 at a favorable temporal-spatial resolution of 41.55 ± 17.46 μm (distance between adjacent cells) or 0.97 ± 0.41 ms (time interval between adjacent cells). With a laboratory-made nebulization device, a cell measurement efficiency up to 42.1 ± 7.2% is achieved in ICP-MS assay. Analysis of Au nanoparticles (AuNPs) in living K562 cells after incubation illustrates obvious diversification of AuNPs among cells. The ultrahigh throughput and cell measurement efficiency generate massive data on single-cell assay, make statistical analysis more comprehensive, and enable interpreting extremely subtle differences among individual cells.