Abstract: Monoenergetic electron beams with the energy of (23.0±0.8) MeV and the charge of 6 pC were generated by using 2 TW and 80 fs laser pulses interacting with underdense plasmas. The beam’s normalized divergence angle is merely 92 mrad, which is at least 5 times smaller than the published laser plasma acceleration experiment results. 2D simulation and experiment data analysis results show that the significant improvement is due to the smooth transfer from self modulated laser wakefield acceleration to laser wakefield acceleration.