Energy transfer distances from polysilanes bearing alkyl groups to those bearing aromatic groups are estimated by employing heteropolysilane Langmuir-Blodgett (LB) films. In the heteropolysilane films, AL1-LB film (10 layers, poly((hydroxyhexyl)hexylsilane))/I1-LB film (n layers, insulator polymer, (isobutyl methacrylate))/AR1-LB film (10 layers, poly((hydroxyphenyl)butylsilane)), AL1 is selectively excited with 310 nm light and the fluorescence from AR1-LB film is observed, as the number of insulator layers, n, is changed. The results imply that energy does not transfer from AL1-LB film to AR1-LB film when two insulator LB layers (22 Angstrom) are inserted between the two polysilane LB films. The electron transfer distances from polysilanes to (2,2’-(2-(cholan-24-yl)-2,5-cyclohexadiene-1,4-diylidene)-bis(propanedinitrile) (TCNQ1) are also estimated by employing a heteropolysilane LB film, AL1-LB film (10 layers)/I1-LB film (insulator, n layers)/TCNQ1-LB film (10 layers). The electron transfer distance from AL1-LB film to TCNQ1-LB film is determined by observing the decomposition of AL1 (the decrease in the UV absorption) when TCNQ1-LB film is selectively exposed to UV light. It is estimated that electron transfer from AL1-LB film to TCNQ1-LB film occurs through insulators of less than 22 Angstrom thickness.