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As one well-known double-peaked emitter (AGN with double-peaked broad low-ionization emission lines), 3C390.3 has been studied for more than two decades, since clear double-peaked broad balmer lines were reported by Burbidge & Burbidge (1971, spectrogram of 3C390.3) and by Perez et al. (1988, clear spectral lines). Based on double-peaked appearance of the broad lines and characters of long-term variabilities of the broad lines and continuum emission, among those proposed theoretical models for double-peaked emitters (such as binary black hole model: Begelman et al. 1980, Boroson & Lauer 2009, Gaskell 1996, Lauer & Boroson 2009, Zhang et al. 2007, double stream model: Vellieux & Zheng 1991, Zheng et al. 1990, 1991, accretion disk model: Bachev 1999, Chen et al. 1989, Chen & Halpern 1989, Chornock et al. 2010, Eracleous et al. 1995, Flohic & Eracleous 2008, Gaskell 2010, Gezari et al. 2007, Hartnoll & Blackman 2000, 2002, Karas et al. 2001, Lewis et al. 2010, Oke 1987, Perez et al. 1988, Storchi-Bergmann, et al., 2003, Schimoia et al. 2012, Tran 2010), the accretion disk model (double-peaked broad lines coming from central accretion disk) has been widely accepted for the double-peaked emitter 3C390.3 (Chen et al. 1989, Chen & Halpern 1989, 