Heavy metals are not bio-degradable and may accumulate in the body, remaining there for a long time. These heavy metals may have adverse health effects as they may be toxic even at trace levels. In children heavy metals such Pb can reduce brain growth, learning abilities and intelligence. In the present study the concentrations of heavy metals in the environment of Lahore were measured to determine whether they lie within the acceptable limits or not. In order to carry out this purpose, 15 air conditioners filter dust samples from 15 different sites of Lahore were collected Samples were prepared using the Leeds Public Analyst Method.. These samples have been analyzed using instrumental neutron activation analysis (INAA) and flame atomic absorption spectrometry (FAAS). The heavy metals Cd, Cu, Cr, Pb, Ni, Mn and Zn were determined with the help of FAAS while Al, As, Br, Ca, Ce, Co, Cr, Cs, Fe, Hf, Hg, K, La, Lu, Mg, Mn, Na, Nd, Rb, Sb, Sc, Se, Sm, Sn, Sr, Ta, Tb, Ti, U, V, Yb, Zn, and Zr were measured using INAA.