On 14 January he was suspended as a result of a positive doping test, but late Friday the result of the B test showed no traces of banned substances.
This means that Martins is free to train and play matches again for Aalborg, says the club in a press release.
"Of course, the exclusion came as a shock to me, and the past month has been incredibly hard for both me and my family. However, I am extremely happy that the B test proved my innocence, as I have always maintained that it would", says Martins in the press release.
"I have never and would never consider using performance-enhancing substances to gain an advantage, and I therefore sincerely hope that the cause of this error will be investigated thoroughly, so that the whole process can be clarified and see the light of day."
The suspension ended up costing Miguel Martins participation at the recently held Handball World Championships where Portugal for the first time in history reached the Final Four.
Aalborg were also relieved to receive the news Friday evening.
"We are both relieved and happy on Miguel's behalf and are of course very satisfied that he can train and play matches with the team again, which is hugely positive in view of the packed program we are for the rest of this season", says Aalborg director Jan Larsen in the press release.
"Having said that, we still lack a more detailed explanation of how the suspension could happen, and that a player can thus be excluded from a number of important matches and great experiences, as well as being exposed to tremendous personal pressure."
The club still has faith that the International Handball Federation and the International Anti-Doping Agency will investigate the matter thoroughly, so that similar mistakes do not happen in the future.
Miguel Martins can potentially be back in action as early as Saturday afternoon when Aalborg faces Sønderjyske in the Danish Cup tournament.