The Welsh Government said "current and historic" cases should be investigated after new claims of sexual assault, sexual harassment and bullying emerged.
BBC Wales Live research found staff working for AMs made two claims of sexual assault against BBC staff and one against a politician.
Six members of staff said they had experienced bullying or sexual harassment at work.
The BBC said it would take the allegations "seriously".
The anonymous allegations were made in response to a questionnaire sent to all 247 support staff of assembly members as part of research by BBC Wales Live in April.
It asked about sexual harassment and bullying in the Senedd in Cardiff Bay and constituency offices and received 30 responses.
Welsh Government Minister Julie James said "inappropriate behaviour" needed to be "called out and dealt with".
She added: "We need to look at current issues but also historic issues because if there is a reputational problem we need to address that as well."
Three who responded said they had been sexually assaulted at work:
- One said they had been "inappropriately touched" by a person working for the BBC
- Another said they had been sexually assaulted by a member of BBC staff
- One said they had been sexually assaulted by an AM
The questionnaire was anonymous and did not include any names. This meant the specific claims could not be verified.
Additional allegations of inappropriate behaviour were made by six members of staff who said they had experienced bullying or sexual harassment at work.
- One said they were "accosted aggressively by a BBC journalist"
- Another said it was an "awful toxic environment" and that the AM was "the judge, jury and executioner and if they are the bully there's nothing that can be done"
- One respondent said they were "shouted or sworn at" and "threatened or intimidated"
There was also criticism about how complaints were dealt with.
Other responses were more positive saying the atmosphere at the assembly was "friendly, approachable and very rewarding" and "a lot better than it has been portrayed in the media".
On Tuesday the presiding officer Elin Jones said there was a "serious" problem with inappropriate behaviour at the Welsh assembly.
A separate survey of staff and AMs by The Assembly Commission - the body which runs the assembly - found 37 people had experienced incidents of inappropriate behaviour.
A further 37 who experienced or witnessed such behaviour said they did not report it.
In total, 128 responses were received with a participation rate of 16.8% - around one in six.
Analysis by BBC Wales Political Correspondent Arwyn Jones
There is clearly a sensitivity here due to the death of sacked Welsh Government minister Carl Sargeant a few days after he insisted he would clear his name following allegations of "unwanted attention, inappropriate touching or groping".
But those who spoke at the time supporting the rights of other women to make complaints against politicians in Cardiff Bay have faced what they call "a barrage of attacks" on social media and don't feel it's possible to discuss the subject.
So why is that the case? Some of it is a result of fear about the "backlash", but there are other reasons too.
We've had 30 responses, which is a typically low number for a questionnaire like this. So while it isn't representative it gives us an insight into life for some in Welsh politics.
It's also reinforced by the findings of the assembly's own questionnaire.
In response to the BBC research, Director of BBC Wales Rhodri Talfan Davies said: "Clearly these are serious allegations and we are going to look very carefully at the information that has been broadcast. It is phenomenally difficult to verify these types of allegations, they are given in confidence and we need to respect that.
"I have been in this job for seven years and I have never heard allegations of this nature against any individual member of staff but we are not complacent - if we receive any information that we can investigate then we will do that robustly and we will do it thoroughly."
In a statement, the Welsh Assembly pointed to the recently passed Dignity and Respect policy, where any complaints about anyone working at or visiting the Assembly would be investigated.
It added: "Inappropriate behaviour of any kind has no place in the Assembly. The testimonies of the women interviewed by Wales Live and the results of the BBC survey coupled with our own survey results, clearly demonstrate that much more must be done to ensure that the National Assembly for Wales is a safe environment for those who work here, for those who visit the estate and for anyone who has dealings with us.
"For those who are subject to inappropriate behaviour, in whatever form that takes, we must ensure that they feel able to come forward to seek advice and support, as well as to make a complaint should they choose to do so."
The BBC said anyone with further information could come forward anonymously or via independent organisation Expolink.
Wales Live, BBC One Wales on Wednesday at 22:30 BST