NOVELTY - A nonaqueous electrolyte solution comprises compound (A) which does not have aliphatic substituent having unsaturated bond, but has silicon-silicon bonding, and compound (B) chosen from carbonate ester having unsaturated bond, metal complex compound (I), compound having sulfur-oxygen bond, compound having cyanate group, monofluorophosphate, difluorophosphate, fluorosulfonic acid salt and imide salt.    USE - Nonaqueous electrolyte solution used in nonaqueous electrolyte secondary battery (claimed) used as vehicle-mounted power supply and fixed type power supply.    ADVANTAGE - The nonaqueous electrolyte solution provides secondary batteries with excellent low temperature charging/discharging cycle characteristics.    DETAILED DESCRIPTION - A nonaqueous electrolyte solution comprises compound (A) which does not have aliphatic substituent having unsaturated bond, but has silicon-silicon bonding, and compound (B) chosen from carbonate ester having unsaturated bond, metal complex compound of formula (I), compound having sulfur-oxygen bond, compound having cyanate group, monofluorophosphate, difluorophosphate, fluorosulfonic acid salt and imide salt. The nonaqueous electrolyte solution is used in nonaqueous electrolyte secondary battery provided with negative electrode and positive electrode in which occlusion and discharge of a metal ion are possible.    M=1-6C hydrocarbyl optionally containing hetero atom, transition metal of group 13, 14 or 15;    Z power(a+)=metal ion, proton or onium ion;    a,b=1-3;    l=b/a;    m=1-4;    n=1-8;    t=0-1;    p=0-3;    q,r=0-2;    R1=1-20C hydrocarbyl optionally containing halo or hetero atom, or X3R4;    two or more R1=ring;    R2=1-6C hydrocarbyl optionally containing hetero atom, or direct bond;    X1-X3=O, S, or NR5;    R3-R5=1-10C hydrocarbyl optionally containing hetero atom;    or two or more R3,R4=ring;and    Y1,Y2=C, S or Si.    When Y1 or Y2 is C or Si, q or r is 0 or 1, respectively; (ii) When Y1 or Y2 is S, q and r are 2, respectively; (iii) When M is 1-6C hydrocarbyl containing hetero atom, Z power (a+) does not exist, a,b,l,n are 0, m is 1, t is 0-1, p is 0-3, q and r are 0-2. An INDEPENDENT CLAIM is included for nonaqueous electrolyte secondary battery, which consists of the electrolyte solution, carbon-type negative electrode and positive electrode which discharges and occludes metal ion.