A focus window determining method, comprising: when a face is detected in a to-be-photographed image, determining to use a face area as a current focus window; detecting a preset location in the face area, and adjusting a width of the current focus window according to the preset location in the face area; stretching a length of the current focus window according to at least a first preset ratio and a second preset ratio, wherein a focus window obtained after stretching the length of the current focus window according to the first preset ratio is a first focus window, and a focus window obtained after stretching the length of the current focus window according to the second preset ratio is a second focus window; calculating a contrast value of an image in the first focus window and a contrast value of an image in the second focus window; and determining a final focus window according to the contrast value of the first window and the contrast value of the second window; and when a face is not detected, placing a current focus window in a central area of the image in a preset size and determining whether a contrast value of the image in the current focus window is less than a first threshold and if it is determined that the contrast value of the image in the current focus window is less than the first threshold, determining that the image in the current focus window is a flat area, enlarging the current focus window according to multiple preset ratios to obtain corresponding multiple focus windows; calculating for each focus window a corresponding contrast value; and determining a final focus window according to the contrast values corresponding to the multiple focus windows. when a face is detected in a to-be-photographed image, determining to use a face area as a current focus window; detecting a preset location in the face area, and adjusting a width of the current focus window according to the preset location in the face area; stretching a length of the current focus window according to at least a first preset ratio and a second preset ratio, wherein a focus window obtained after stretching the length of the current focus window according to the first preset ratio is a first focus window, and a focus window obtained after stretching the length of the current focus window according to the second preset ratio is a second focus window; calculating a contrast value of an image in the first focus window and a contrast value of an image in the second focus window; and determining a final focus window according to the contrast value of the first window and the contrast value of the second window; and determining to use a face area as a current focus window; detecting a preset location in the face area, and adjusting a width of the current focus window according to the preset location in the face area; stretching a length of the current focus window according to at least a first preset ratio and a second preset ratio, wherein a focus window obtained after stretching the length of the current focus window according to the first preset ratio is a first focus window, and a focus window obtained after stretching the length of the current focus window according to the second preset ratio is a second focus window; calculating a contrast value of an image in the first focus window and a contrast value of an image in the second focus window; and determining a final focus window according to the contrast value of the first window and the contrast value of the second window; and when a face is not detected, placing a current focus window in a central area of the image in a preset size and determining whether a contrast value of the image in the current focus window is less than a first threshold and if it is determined that the contrast value of the image in the current focus window is less than the first threshold, determining that the image in the current focus window is a flat area, enlarging the current focus window according to multiple preset ratios to obtain corresponding multiple focus windows; calculating for each focus window a corresponding contrast value; and determining a final focus window according to the contrast values corresponding to the multiple focus windows. placing a current focus window in a central area of the image in a preset size and determining whether a contrast value of the image in the current focus window is less than a first threshold and if it is determined that the contrast value of the image in the current focus window is less than the first threshold, determining that the image in the current focus window is a flat area, enlarging the current focus window according to multiple preset ratios to obtain corresponding multiple focus windows; calculating for each focus window a corresponding contrast value; and determining a final focus window according to the contrast values corresponding to the multiple focus windows.