The present invention relates to a method and apparatus for multi-band testing. A first multi-carrier signal in a lower frequency band of the maximum radio bandwidth of the multi-band transmitter is received. The first multi-carrier signal has a narrowband carrier located at the higher edge of the lower frequency band and a wideband carrier. A second multi-carrier signal in a higher frequency band of the maximum radio bandwidth of the multi-band transmitter is received. The second multi-carrier signal has a narrowband carrier located at the lower edge of the higher frequency band and a wideband carrier. Between the lower frequency band and the higher frequency band, a frequency gap is present. The wideband carrier in the lower frequency band is located in the lower frequency band such that its third order intermodulation product with the narrowband carrier in the lower frequency band is generated in the middle of the frequency gap. The wideband carrier in the higher frequency band is located in the higher frequency band such that its third order intermodulation product with the narrowband carrier in the higher frequency band is generated in the middle of the frequency gap. The transmitter test is performed with the first and second signal.