NOVELTY - A positively-photosensitive siloxane composition is obtained by hydrolyzing and condensing silane compound of formula (i), and contains polysiloxane (I). The polysiloxane contains at least one of polysiloxane (Ia, Ib and Ic). The melt rate of film formed using polysiloxane (Ia) after prebaking with respect to 5 wt.% of tetramethylammonium hydroxide aqueous solution is 1000 Angstrom /second or more. The melt rate of film formed using polysiloxane (Ib) after prebaking with respect to 2.38 wt.% of tetramethylammonium hydroxide aqueous solution is 4000 Angstrom /second or more.    USE - Positively-photosensitive siloxane composition is used for cured film for element (all claimed). Uses include but are not limited to solid-state image sensor, anti-reflection film, reflection-preventing board, optical filter, high-intensity light emitting diode, touch panel, solar cell, and optical waveguide.    ADVANTAGE - The positively-photosensitive siloxane composition has high sensitivity and resolution, provides cured film with excellent heat resistance, transparency and electrical-insulating property.    DETAILED DESCRIPTION - A positively-photosensitive siloxane composition is obtained by hydrolyzing and condensing silane compound of formula: R1nSi(OR2)4-n (i), and contains diazonaphthoquinone derivative and solvent, and polysiloxane (I). The polysiloxane contains polysiloxane (Ia, Ib and Ic). The melt rate of film formed using polysiloxane (Ia) after prebaking with respect to 5 wt.% of tetramethylammonium hydroxide aqueous solution is 1000 Angstrom /second or more. The melt rate of film formed using polysiloxane (Ib) after prebaking with respect to 2.38 wt.% of tetramethylammonium hydroxide aqueous solution is 4000 Angstrom /second or more. The melt rate of film formed using polysiloxane (Ic) after prebaking with respect to 2.38 wt.% of tetramethylammonium hydroxide aqueous solution is 200-3000 Angstrom /second or more.    R1=1-20C linear, branched, cycloalkyl in which arbitrary methylene is optionally substituted with oxygen, 6-20C aryl in which arbitrary hydrogen is optionally substituted with fluorine;    n=0 or 1;and    R2=1-5C alkyl group.