According to one embodiment, a voice keyword detection apparatus includes a memory and a circuit coupled with the memory. The circuit calculates a first score for a first sub-keyword and a second score for a second sub-keyword. The circuit detects the first and second sub-keywords based on the first and second scores. The circuit determines, when the first sub-keyword is detected from one or more first frames, to accept the first sub-keyword. The circuit determines, when the second sub-keyword is detected from one or more second frames, whether to accept the second sub-keyword based on a start time and/or an end time of the one or more first frames and a start time and/or an end time of the one or more second frames.