We have studied the relationship between the film structure and the conditions for film preparation of a hybrid film of a D-pi-A zwitter ionic molecule and a sodium montmorillonite. The films were obtained by means of the modified Langmuir-Blodgett technique. As for the D-pi-A zwitter ionic molecule, indoline-TCNQ intramolecular charge-transfer compound (ind-TCNQ) was employed. We have prepared various kinds of hybrid-films by changing a parameter during the film preparation. The films thus obtained have been characterized by means of the second-harmonic generation measurements. As a result, a surface pressure at film deposition plays an important role for maintaining the film structure.