Method for controlling a game using an output from a first sensor which is an acceleration sensor or a gyrosensor provided in a first control unit and an output from a second sensor which is an acceleration sensor or a gyrosensor provided in a second control unit, the first and the second control unit each being separately and freely moveable by one hand, the method comprising: a first detection step for detecting an output from the first sensor; a second detection step for detecting an output from the second sensor; a processing step for processing the output of the first sensor and the output of the second sensor; and game control step for executing game control using the output of the processing step to control a single game object; first motion operation detection step for detecting a motion of the first control unit based on an output from the first sensor; second motion operation detection step for detecting a motion of the second control unit based on an output from the second sensor; characterized in that the method further comprises: simultaneous input detection step for detecting, based on the detection results of the first motion operation detection step and the second motion operation detection step, whether or not a motion of the second control unit was detected within a simultaneous input acceptance time period which is counted from a timing determined in relation with the detection of a motion of the first control unit; and and in that the game control step comprises a step for executing first game processing when the simultaneous input detection step detects that the motion of the second control unit was detected within the simultaneous input acceptance time period after the motion of the first control unit was detected; and wherein the first motion operation detection step does not newly detect a motion of the first control unit until an acceptance prohibition time period passes after a timing determined in relation with the detection of the motion of the first control unit; and the second motion operation detection step does not newly detect a motion of the second control unit until the acceptance prohibition time period passes after the motion of the second control unit was detected. a first detection step for detecting an output from the first sensor; a second detection step for detecting an output from the second sensor; a processing step for processing the output of the first sensor and the output of the second sensor; and game control step for executing game control using the output of the processing step to control a single game object; first motion operation detection step for detecting a motion of the first control unit based on an output from the first sensor; second motion operation detection step for detecting a motion of the second control unit based on an output from the second sensor; characterized in that the method further comprises: simultaneous input detection step for detecting, based on the detection results of the first motion operation detection step and the second motion operation detection step, whether or not a motion of the second control unit was detected within a simultaneous input acceptance time period which is counted from a timing determined in relation with the detection of a motion of the first control unit; and and in that the game control step comprises a step for executing first game processing when the simultaneous input detection step detects that the motion of the second control unit was detected within the simultaneous input acceptance time period after the motion of the first control unit was detected; and simultaneous input detection step for detecting, based on the detection results of the first motion operation detection step and the second motion operation detection step, whether or not a motion of the second control unit was detected within a simultaneous input acceptance time period which is counted from a timing determined in relation with the detection of a motion of the first control unit; and and in that the game control step comprises a step for executing first game processing when the simultaneous input detection step detects that the motion of the second control unit was detected within the simultaneous input acceptance time period after the motion of the first control unit was detected; and wherein the first motion operation detection step does not newly detect a motion of the first control unit until an acceptance prohibition time period passes after a timing determined in relation with the detection of the motion of the first control unit; and the second motion operation detection step does not newly detect a motion of the second control unit until the acceptance prohibition time period passes after the motion of the second control unit was detected.