Cyclists now face a €50 spot fine for not wearing a helmet but this can rise to €500 if the issue ends up in court.
The police and supporters of the law now being enforced say it will make cycling safer, but critics say it unfairly blames and restricts those using alternative transport.
Jason Senekkis, research assistant at the European University Cyprus, told the Cyprus Mail that the law now means cyclists on paths in parks such as the Grammiko in the capital will be fined for not wearing a helmet.
But police arguing in favour of the law point to the four cyclists and one e-scooter user who died last year, none of whom were wearing helmets.
Senekkis, however, emphasised that four of those incidents saw cars crash into the cyclists with incredible force, while another had fallen from a six-metre height.
Some also argue that placing restrictions on cyclists will further dissuade people from using alternative means of transport to cars.
The regulation further stipulates that not just any helmet will do, as it must comply with the CYS EN 078:2012+A1 standard, explicitly state that it is intended at least for cyclists and be marked with a Declaration of Conformity: CE.
Elsewhere, stricter rules have been enforced for e-scooters, as only those aged 14 and older are allowed to ride them and if it allows for another passenger, the second individual should be above the age of 12.
There is a mandatory requirement to use a helmet as well as clothing with fluorescent indicators. At the very least, the e-scooter should have brakes, lights at the back and front, as well as a bell, the transport ministry said.
Additionally, the maximum speed should be at 20km/h. When riding in a square or pavement, the speed should not go higher than 10km/h. Priority should always be giving to pedestrians.
Use of an e-scooter in a square or pedestrian area is only permitted if there is an indicative horizontal or vertical signpost, the transport ministry specified.