A data frame sending method and apparatus for effectively improving sending efficiency by, acquiring a basic speed set, determining a current sending speed which is the maximum speed in a candidate speed set, and the candidate speed set is the set of elements from the basic speed set and whose packet sending success rate is greater than a threshold, acquiring an aggregation length value according to the current sending speed, where the aggregation length value is the maximum length of a frame that can be sent at the current sending speed, determining multiple medium access control (MAC) protocol data units (MPDUs) from to-be-sent MPDUs according to the aggregation length value, and aggregating the multiple MPDUs to obtain an aggregate MAC protocol data unit (A-MPDU), where a length of the A-MPDU is less than or equal to the aggregation length value, and sending the A-MPDU at the current sending speed.