Spergularia macrotheca is a species of flowering plant in the family Caryophyllaceae known by the common name sticky sandspurry.

[1] It is native to western North America from British Columbia to Baja California, where it grows in many types of moist coastal and inland habitat, often in alkaline and saline substrates.

It may be found in marshes, alkali flats, beaches, meadows, seeps, and vernal pools.

It is a perennial herb producing a narrow stem up to 40 centimeters long with a woody, thickened base and taproot.

The small flowers have five pointed sepals and five oval white to lavender-pink petals.