In this study a bioactive glass based on both H3BO3 and P2O5 doped with ZnO, different La2O3 and an amount of CdCO3 were synthesized by melting quenching method and characterized via XRD, FTIR, visible-UV spectroscopy, SEM and EDX before and after immersion in SBF solution for 7 and 14 days. The aim of this paper is to study the bioactivity of the bioactive glass with composition (54-X) H3BO3 + 39.98 ZnO + 0.02 CdCO3O + 6 P2O5 + X La2O3 with varied La2O3 content (X = 0.1, 0.2, 0.3, and 0.5 wt%). The bioactivity is assessed via immersion in SBF to assess the formation of hydroxyapatite layer. The pH is monitored through the immersion and the characterization results were analyzed. It was found that the current composition is bioactive and hydroxyapatite layers were formed on the surfaces of the samples during immersion for 7 and 14 days. lanthanum with its low concentration in the composition acted as a modifier and have a potential in stabilizing the formed HA layer. XRD of the prepared samples revealed that the amorphous nature of all prepared samples with lanthanum phosphate and lanthanum borate phases. FTIR and UV-visible spectroscopy showed the presence many phases due to the presence lanthanum as a modifier which provide more energy level transitions in the samples. pH and EDX shows that the samples interacted with the SBF via ions exchange and formed HA layer which was imaged by SEM for the samples of higher concentration of lanthanum. High contents of lanthanum have high potential in HA formation and this was proven by the detected high atomic percent of Ca and P after immersed in SBF for 14 days. It created amorphous smooth surface with agglomeration and fibrous structure. Formation of HA layer at the surface may resist ion release, ion echange and HA formation processes were active simultaneously. The findings of this study will contribute to a better understanding of lanthanum-based bioactive glasses and their potential use in biomedical applications.