A radio physical layer protocol data unit (PPDU) sending method includes: obtaining, a radio physical layer protocol data unit (PPDU), wherein the PPDU includes a high efficiency-signal field A (HE-SIG-A) and a high efficiency-signal field B (HE-SIG-B), the HE-SIG-A includes a field indicating a quantity of orthogonal frequency division multiplexing (OFDM) symbols in the HE-SIG-B, and wherein a value of the field indicates one of the following: that the quantity of OFDM symbols included in the HE-SIG-B is greater than or equal to 16, or the quantity of OFDM symbols included in the HE-SIG-B; and sending the PPDU.