Mark Hillman, 26, was shot twice in the back and found on a pavement in Lloyd Close, Everton, on 27 April.
A 35-year-old man from Anfield has been arrested on suspicion of conspiracy to commit murder and assisting an offender.
Two women previously arrested in connection with the murder inquiry, have been released on bail pending further enquiries.
A man has been arrested over the fatal shooting of a man in Liverpool.