The council said it accepted the move may upset grieving families, but that it hoped they would understand the reasons for it at a time "national crisis".
No more than 10 people will be able to attend services at Wakefield or Pontefract Crematoria for the foreseeable future, while the UK battles coronavirus.
A maximum of 20 mourners will be allowed to attend burial and graveside services that are run by Wakefield Council and they will be asked to remain two metres apart to observe social distancing rules.
The limits are in force as of Wednesday this week.
Wakefield Council’s acting chief executive, Andrew Balchin, said: "We fully appreciate that introducing these new rules on the numbers of mourners that can attend the funeral of a loved-one will be very upsetting for many bereaved families, and we offer them our sincere sympathies at their time of loss.
"We hope that people will understand that at this time of national crisis, we have to make these very difficult decisions.
"We have carefully considered all the latest advice and information from the government.
"Our priority is to keep people safe, including mourners, funeral directors and council staff by taking these actions to reduce the risk of spreading the virus."
Local Democracy Reporting Service