There is only one sharp in G minor: the F# in the harmonic and melodic minors.
The key signature for G minor is two flats, so the answer to your question is pretty much zero. Its leading tone, however, is F-sharp, always written with an accidental, so I suppose one could consider that there is one sharp in G minor, although not in the key signature.
Please also see the related link about the G minor scale.
5 sharps. F C G D A
There are four sharps in C sharp minor. These sharps are C# D# F# and G#. The harmonic minor also has B#. (which is C)
B Major (and G sharp minor) has five sharps, but B minor only has two sharps (like D major).
The key with 7 sharps is B major. In this key, the notes are B, C#, D#, E, F#, G#, and A#. The relative minor of B major is G# minor, which also contains 7 sharps.
C major (no sharps or flats)Sharp Keys:G Major/E minor (1 sharp)D Major/B minor (2 sharps)A Major/F-sharp minor (3 sharps)E Major/C-sharp minor (4 sharps)B Major/G-sharp minor (5 sharps)F-sharp Major/D-sharp minor (6 sharps)C-sharp Major/A-sharp minor (7 sharps)Flat Keys:F Major/D minor (1 flat)B-flat Major/G minor (2 flats)E-flat Major/C minor (3 flats)A-flat Major/F minor (4 flats)D-flat Major/B-flat minor (5 flats)G-flat Major/E-flat minor (6 flats)C-flat Major/A-flat minor (7 flats)These are all the possible keys you can write in, enharmonic keys are italicised.
There are no sharps in the key signature, but in the harmonic minor there is a G#.
B major, or G sharp minor. The sharps are F, C, G, D and A. F#, C#, G#, D#, A#
5 sharps. F C G D A
F-sharp minor contains three sharps: F, C, and G.
B Major and G sharp minor. The sharps are F, C, G, D, and A sharp, in that order.
G minor contains two flats: B and E.
There are four sharps in C sharp minor. These sharps are C# D# F# and G#. The harmonic minor also has B#. (which is C)
B Major (and G sharp minor) has five sharps, but B minor only has two sharps (like D major).
A major has 3 sharps, A minor has no sharps or flats.
The natural minor has 5 and the harmonic minor has 4 and a double sharp.
In A harmonic minor, there is just one sharp (G sharp).
The key of G-sharp minor has 5 sharps (it's the relative to B major). G-flat minor is a key that only exists in theory, because that key signature would contain 9 flats. The limit on flats or sharps in a key is 7.