In this investigation, ignition processes of methane (CH(4) > 98%) and propane (C(3)H(8) > 95%) using a high-temperature oxidizer (T(oxi) > T(ai)) with a varying oxygen concentration (z(O2) - 0.05 divided by 0.21), applying two types of experimental installations, viz. a constant-volume bomb (CVB) and a co-flow reactor (CFR) were investigated. The influence of the initial temperature of the oxidizer (for methane T(oxi) = 960 divided by 1234 K and for propane T(oxi) = 803 divided by 1055 K), the equivalence ratio and oxygen concentration in the oxidizer on ignition of gaseous fuels is analyzed and discussed. It is shown that in order to achieve an effective reaction of ignition (taking into account the minimum value of ignition delay time tau(ig) and maximal value of the increment of temperature Delta T) the oxidizer temperature need not be maximized. There are optimal values of temperature of the oxidizer (for methane T(oxi) approximate to 1100 K and for propane T(oxi) approximate to 950 K) in which the parameters mentioned above reach their extreme values. (C) 2010 Elsevier Ltd. All rights reserved.