This disclosure provides a Scheduling Request transmission method (10) for decoupled downlink-uplink in heterogeneous network, where the heterogeneous network comprises at least two cells in charge of downlink and uplink transmission separately and connected with any backhaul, the method comprising: determining (11) a positive Data Scheduling Request, D-SR, is to be transmitted in a current D-SR's subframe together with HARQ-ACK/NACK on PUCCH using PUCCH format 1a/1b/3; transmitting (12) a HARQ-ACK/NACK in the current D-SR's subframe on PUCCH together with a negative D-SR using PUCCH format 1/1a/1b or format 3 while transmitting a Scheduling Request, SR, in a next SR's subframe subsequent to the current D-SR's subframe. In this method, the Scheduling Request (SR) of the UEs can be correctly detected in the Pico base station to trigger UL transmission in decoupled UL/DL scenario in various case and any kinds of backhaul can be supported.